Our live coverage of the war in Ukraine has moved here.
After enduring a brutal assault for more than a month, Ukrainian fighters in the besieged southeastern port city of Mariupol rejected a Russian deadline to surrender on Sunday and vowed to fight on.
Here's what you need to know:
- The situation on the ground: Mariupol has been surrounded by Russian troops since March 1, with much of the city and its immediate surroundings reported to be largely under Russian control. However, Ukrainian Prime Minister Denys Shmyhal said Mariupol has not yet fallen. Ukrainian troops trapped in the city are holding out despite overwhelming odds — but they are confined to pockets of resistance, and their numbers are unclear.
- Russian forces to close entry: Mariupol will be closed for entry and exit starting on Monday and men remaining in the city would be "filtered out," Russian forces said, according to an adviser for the mayor. The Russians had begun issuing passes for movement within the city, the adviser Petro Andriushchenko said, adding that citizens will not be able to go out onto the streets or move between districts without one. CNN cannot independently verify the claims.
- Russia's demand: Russia's Ministry of Defense called on the Ukrainian soldiers still in Mariupol to lay down arms surrender by 1 p.m. local time on Sunday, warning anyone still resisting after the deadline "will be eliminated." It also said trapped "foreign mercenaries who joined the Ukrainian forces," including Europeans and Canadians, "will be eliminated" if there is further resistance.
- The Ukrainian response: "There are still our military forces, our soldiers, so they will fight until the end and as for now they are still in Mariupol," Shmyhal said on Sunday. An adviser to Mariupol's mayor also rejected the Russian ultimatum, saying, "as of today, our defenders continue to hold the defense." The Russian defense ministry confirmed their ultimatum had been ignored.
- Red line in negotiations: Ukrainian Foreign Minister Dmytro Kuleba said on Sunday the situation in Mariupol "may be a red line" in negotiations with Russia. “The city doesn’t exist anymore. The remaining of the Ukrainian army and a large group of civilians are basically encircled by the Russian forces," he said on CBS' “Face the Nation."
- Civilians and casualties: Though many residents have fled, an estimated 100,000 people still remain in Mariupol and its immediate surroundings. The military governor of Donetsk region, where Mariupol is located, said on Tuesday up to 22,000 people may have died in the city. CNN cannot verify the figures, as there are no independent casualty numbers from the fighting in the city available.
Ukrainian President Volodymyr Zelensky warned of an incoming offensive by Russian forces in the eastern part of the country, during a video address on Sunday.
“Russian troops are preparing for an offensive operation in the east of our country. It will begin in the near future,” Zelensky said.
“They want to literally finish off and destroy Donbas. Destroy everything that once gave glory to this industrial region. Just as the Russian troops are destroying Mariupol, they want to wipe out other cities and communities in the Donetsk and Luhansk regions."
In the city of Kharkiv: Zelensky said Russian shelling had killed five residents and wounded 15 others on Sunday. He added that in the last four days, 18 people in total have been killed and 106 have been wounded by Russian shelling of Kharkiv.
“This is nothing but deliberate terror. Mortars, artillery against ordinary residential neighborhoods, against ordinary civilians,” he said.
Zelensky accused Russian forces of committing humanitarian violations in the Kherson and Zaporizhzhia regions in southern Ukraine.
“Torture chambers are built there. They abduct representatives of local authorities and anyone deemed visible to local communities. They blackmail teachers. They steal money provided for paying pensions. Humanitarian aid is blocked and stolen. They create starvation,” he said.
CNN cannot independently verify the claims made by Zelensky.
Zelensky also reiterated his plea for allies to cut off Russian oil supplies in his address.
“The need for an embargo on oil supplies from Russia is growing every day. Everyone in Europe and America already sees Russia openly using energy to destabilize Western societies. Russia's bet on chaos in fuel markets should not succeed,” he said.
It's hard to find out what's going on inside Russia as its attack on Ukraine rages.
So those looking for news of what's going there are looking to neighboring Estonia, according to CNN International Correspondent Scott McLean, reporting from its capital Tallinn.
Estonia, a country of 1.3 million people, has taken in 30,000 Ukrainian refugees since the war began.
Like Ukraine, it too was a former Soviet state, and still has a large Russian-speaking population, and a well-founded fear of Russian aggression. The majority of its population is ethnically Russian, especially in the towns just across the Narva river, which separates the country from Russia. Many of Narva's older residents don't speak Estonian well, if at all.
"In the absence of a whole lot of Russian language media in Estonia," Mclean said. "Russian state media has been left to fill the void, giving people a steady dose of Kremlin propaganda."
But now even that source has been cut off since the invasion. When Russia invaded Ukraine on Feb. 24, Estonia blocked many Russian news outlets and TV channels.
"Many people here [are] buying some systems to pick up Russian channels," said Vladimir Zavoronkov, a city council chairman in Narva, Estonia's third-largest city, which is located on its border with Russia.
Many are buying antennas in electronic stores to pick up Russian channels and the more technologically-advanced are setting up their own VPNs, he added.
Read the full story:
The Polish government recorded an eight-hour waiting period on Sunday at the Poland-Belarus border for trucks leaving the EU following a sanctions deadline on Saturday.
Drone footage from Saturday showed freight trucks backed up for miles on the road from Poland into Belarus hours before the sanctions went into effect.
The EU has imposed a full ban on Russian and Belarusian freight road operators working in the EU. This was agreed as part of the fifth round of sanctions against Russia over the invasion of Ukraine.
The ban came into effect on Saturday, April 16, and included exceptions for agriculture and food products, humanitarian aid as well as energy.
The northeastern Ukrainian city of Kharkiv endured another day of heavy shelling, according to regional officials.
Oleg Synegubov, head of the Kharkiv regional administration, said on Telegram: "Today, in broad daylight, there were shellings of the central part of the city, the residential area of Saltivka from MLRS [multiple rocket systems] and artillery. Unfortunately, 20 people were injured, 5 people were killed. Apartment buildings and other civilian infrastructure were damaged."
Ihor Terekhov, the city's mayor, said residential areas came under attack in the morning, and missiles were fired at the city center in the afternoon. He said dozens of buildings had been damaged, and the casualties included dead and wounded.
Terekhov said the Russians had not given up on "attempts to destroy the civilian population of Kharkiv, sow panic in the city and break our spirit. Still, the will of Kharkiv, the will of us Ukrainians, cannot be harmed by the enemy. Today, I was convinced of this when I saw how a medic covered a wounded woman during the shelling."
Writing on his Telegram channel, Terekhov said Russian forces "continue to bombard the city furiously. Therefore, I urge you again, if possible, to stay in the shelter and metro stations."
The State Emergency Services said on Sunday afternoon, "18 addresses in Kharkiv were hit as a result of enemy shelling in the central part of the city. Apartments on the fourth and fifth floors were on fire in a five-story building." It said 160 firefighters and 33 units of equipment were involved in extinguishing the fires.
Synegubov said despite the attacks, Ukrainian forces were pushing the Russians back to the east of the city. He claimed several villages had been liberated some 25 miles (40 kilometers) to the southeast of Kharkiv.
If true and if the Ukrainian gains east of Kharkiv are sustained, Russian efforts to resupply forces being gathered in eastern Ukraine for an offensive in Donbas might be hampered. Last week Ukrainian special forces destroyed a bridge on one resupply route south of Kharkiv.
An adviser to Mariupol's mayor said Russian forces have announced the besieged city would be closed for entry and exit on Monday, warning men remaining in the city would be "filtered out."
Petro Andriushchenko, the mayor's adviser, said on Telegram on Sunday Russian forces had begun issuing passes for movement within the besieged city, posting a photo purportedly showing residents lining up for the passes.
"Hundreds of citizens have to stand in a line to get a pass, without which it will be impossible not only to move between the districts of the city, but also to go out on the streets starting next week," he said.
In a separate statement Saturday, Andriushchenko said Russian forces announced the city would be "closed for entry/exit for everyone from Monday, but there will also be a ban on moving around the districts for a week." Andriushchenko added, according to information received from inside the city, men in the city will be subject to "filtration" -- relocated for screening by Russian forces.
CNN cannot independently verify the claims by Andriushchenko, who is not in Mariupol but works to gather information collected from people in the city, which has been under a weeks long siege.
Ukrainian and US officials have alleged Russian forces have carried out filtration of civilians in areas under their control, biometrically screening them, confiscating their phones and, in some cases, deporting them against their will into Russia. The Mariupol City Council has alleged filtration was part of a broader effort by Russia to cover up potential war crimes carried out in the city.
Ukrainian forces defending the city earlier rebuffed an ultimatum from the Russian Ministry of Defense calling on Ukrainian soldiers in the city to surrender.
Ukrainian President Volodymyr Zelensky told CNN that Ukraine is not willing to give up territory in the eastern part of the country to end the war with Russia, and Ukraine's military is prepared to fight Moscow's military in the Donbas region in a battle he says could influence the course of the entire war.
Zelensky said in an exclusive interview Friday with CNN's Jake Tapper from the office of the president in Kyiv that his country has no guarantee that Russia wouldn't try again to seize Kyiv if it is able to capture Donbas.
"This is why it is very important for us to not allow them, to stand our ground, because this battle ... it can influence the course of the whole war," Zelensky said.
Here are more of the latest headlines from the Russia-Ukraine conflict:
- Russian forces “gradually withdrawing” from captured Borivs'kyi district: While Russian forces are still in complete control of the Borivs'kyi district in Ukraine’s Kharkiv region, Moscow's troops are "gradually withdrawing" from the area in the direction of Donetsk region, the Borova village council said in a statement on Telegram on Sunday. “There is no mobile connection and no Internet, which are impossible to restore as the territory is occupied by the Russians,” it said, adding that “some places are left without electricity and gas.”
- Russian shelling hits church in Luhansk region: Serhii Haidai, the head of the Luhansk region military administration, said Russian shelling hit a church in the eastern Ukrainian city of Severodonetsk. "The orcs [derogatory Ukrainian term for Russian troops] shelled the church in Severodonetsk on Palm Sunday," Haidai said. Many Ukrainians observed Palm Sunday on April 17 in accordance with the Julian calendar.
- Mariupol “may be a red line” in negotiations with Russia, Ukraine’s foreign minister says: Ukrainian Foreign Minister Dmytro Kuleba said on Sunday that the "situation" in Mariupol “may be a red line” in negotiations with Russia. “The situation in Mariupol is both dire -- militarily -- and heartbreaking,” Kuleba said on CBS' “Face the Nation." He added: “The city doesn’t exist anymore. The remaining of the Ukrainian army and a large group of civilians are basically encircled by the Russian forces. They continue their struggle, but it seems from the way the Russian army behaves in Mariupol, they decided to raze the city to the ground at any cost."
- Putin believes he’s winning the war: Austria's chancellor said Sunday that Russian President Vladimir Putin believes he's winning the war. Austrian Chancellor Karl Nehammer told NBC's "Meet the Press" that he couldn’t fully explain Putin’s rationale, but did say Putin had his “own war logic," adding the Russian leader “sent me clear messages about his concerns," and that he seemed to have a full grasp of what was unfolding on the ground.
- Five killed in renewed rocket attacks against Kharkiv: Ukrainian officials have reported more civilian casualties Sunday amid rocket and artillery attacks in the Kharkiv and Luhansk regions. Anton Gerashchenko, an adviser to the Minister of Internal Affairs of Ukraine said five people had died and 13 were wounded during renewed rocket attacks against Kharkiv.
- Ukraine's prime minister says Mariupol “still has not fallen”: The Ukrainian forces in the southeastern port city of Mariupol are still fighting and have not surrendered, Ukrainian Prime Minister Denys Shmyhal said on Sunday. “The city (Mariupol) still has not fallen. There are still our military forces, our soldiers so they will fight until the end and as for now they are still in Mariupol,” Shmyhal said on ABC News' "This Week" after a Russian-set deadline for Kyiv's forces in the city to surrender passed on Sunday.
- 41 bodies recovered so far in Borodianka apartment complexes destroyed by Russian shelling: Ukrainian rescuers on Saturday found a body of a civilian in Borodianka, Kyiv, region, while dismantling the rubble of two high-rise apartment buildings destroyed by Russian shelling, raising the number of civilian casualties from the strikes to 41 dead, the country’s State Emergency Service reported on its verified Telegram page on Sunday.