But the Syrian government and opposition groups are not meeting each other face-to-face. Instead, a U.N. special envoy is trying to find common ground between them before too many more people are killed.
The omens, for the moment, are discouraging. On Tuesday, the Syrian opposition issued a statement lambasting what it called the "massive acceleration of Russian and regime military aggression on Aleppo and Homs." The statement was issued by the main Syrian opposition group, called the High Negotiations Committee.
Special envoy Staffan de Mistura said he met Monday with representatives of the High Negotiations Committee. They demanded not just a political solution, he said, but also "facts on the ground, in reduction of the violence, in the fact of the detainees, in the fact of the besieged areas."
De Mistura said a ceasefire is an important goal, but his immediate objectives are to keep the talks going and to get a list of Syrians being detained by the government.
Previous talks have failed. If the Syrian government came through with a list of names, that would be a signal that "there is something different happening," he said.
De Mistura plans to meet with representatives of the Syrian government Tuesday.
The opposition group said it was eager to make progress.
"We are here, we are ready to make this a success, we are ready to start negotiations," High Negotiations Committee spokesman Salim al-Muslat said before the meeting.
Still, the odds against success are formidable.
And U.N. High Commissioner for Human Rights Zeid Ra'ad Al Hussein ruled out an amnesty for the most serious crimes committed in the war.
"In the case of Syria
, we are there to remind everyone that where there are allegations that reach the threshold of war crimes or crimes against humanity that amnesties are not permissible," Hussein said.
"Clearly when looking most recently at the forced starvation of the people of Madaya, and there are 15 other besieged towns and cities, that this is not just a war crime but a crime against humanity if proven in court," he said.
Two earlier rounds of peace talks yielded no lasting ceasefires. Two other U.N. special envoys have come and gone. And all the while, the conflict, which has claimed more than 300,000 lives, has continued to rage.
What U.N. Security Council resolution says
De Mistura is trying to get everyone to agree to a U.N. Security Council resolution
adopted last month. It says the U.N. Security Council is calling for:
• An immediate stop to violence against civilians.
• A Syrian-led political process, facilitated by the United Nations, that would establish "credible, inclusive, and nonsectarian governance" within six months and schedule the drafting of a new constitution.
• Free and fair elections, in accordance with the new constitution, to be held within 18 months.
• An inclusive transitional governing body formed by mutual consent.
• Safe access for humanitarian aid groups trying to reach Syrians in need.
The crisis won't be easy to resolve. Syrian President Bashar al-Assad
has offered no indication he will step aside. And opposition members continue demanding an end to the 44 years of Assad family rule in the country.
The current talks mark the first time in two years that the warring sides in Syria have met to try to end the war. The goal is a ceasefire agreement among all factions in Syria, except ISIS
and al Qaeda-affiliated al Nusra Front -- two terrorist groups that have taken advantage of Syria's instability to gain traction in the country.
Opposition lays out demands
The latest round of talks had been set to begin last week, but it was delayed because of discussions about who should represent the opposition, de Mistura said.
The U.N. special envoy has said his mandate was to involve "the broadest possible spectrum of the opposition." The High Negotiations Committee includes members ranging from a former prime minister to hard-core Islamist groups.
Opposition members have listed their own demands for the regime. They say they want an end to aerial bombardments; the release of prisoners, particularly women and children; and humanitarian access to beleaguered areas.
"It's important to us to see that food goes to our children who are starving to death," said Muslat, the High Negotiations Committee spokesman.
Syrian regime responds
Bashar Jaafari, the Syrian government's lead negotiator and ambassador to the United Nations, said the regime would consider the opposition group's demands.
"Absolutely, because this is part of the agenda that we agreed upon, and that will be one of the very important topics that we will discuss amongst ourselves as Syrian citizens," Jaafari said Sunday.
He said there would be no preconditions, indicating the regime would not do what the opposition asks before the talks are settled.
Jaafari also said it was difficult to discern the terrorists lurking among the opposition.
"We are not holding talks with individuals," he said "We are not having talks with terrorists."
He said authorities had "a big gap" in their ability to distinguish the terrorists among the opposition.
More starvation deaths
As parties work toward an agreement, many Syrians are on the brink of starvation.
The United Nations says 400,000 Syrians badly need food.
At least 16 people have died of starvation in the city of Madaya in recent weeks, according to the aid group Medecins Sans Frontieres, also known as Doctors Without Borders. Those deaths came even after the city received three rare aid convoys of food and medical supplies.
In addition to the deaths, there are 320 cases of malnutrition, the group said
Madaya is a rebel-held city that has been choked off by government blockades and landmines.
Opposition activists have accused Hezbollah, the Lebanese militant and political group, of helping the Syrian government's siege of Madaya. But Hezbollah, in turn, has blamed rebel groups for preventing aid convoys from reaching the town.