(CNN) -- Congress is returning to Washington on Monday after a monthlong summer break to jump right into debate and votes on a resolution giving President Barack Obama the authorization to strike Syria.
Obama said there's no doubt that Syria used chemical weapons on its own civilians on August 21, and he wants to launch attacks, but he first wants to get Congress' approval.
Here are the latest developments Monday:
• State Department deputy spokeswoman Marie Harf said Monday that classified information will help persuade lawmakers to back authorization for military force in Syria.
• The United States will take a "hard look" at a Russian proposal for Syrian President Bashar al-Assad to put his nation's chemical weapons under international control, but "we have some serious skepticism" about whether al-Assad would follow through, Harf said. Saying this has emerged amid a threat of military action, Harf said Monday that al-Assad has resisted efforts to get rid of chemical weapons and this development could be a stalling tactic.
• National Security Adviser Susan Rice said Monday that failing to respond to the chemical weapons attacks in Syria would send a "perverse message": "You can use these weapons blatantly and just get away with it," she said.
• Rice said that only the al-Assad regime had "the capacity" to use chemical weapons in the August 21 attack in the Damascus area. "There's no doubt about who is responsible for this attack," she said Monday.
• Russian Foreign Minister Sergey Lavrov said Russia will urge Syria to put its chemical weapons supply under international control if it will avert U.S. military action.
• Syria "welcomes" Russia's proposal, Syrian Foreign Minister Walid Moallem said in Moscow on Monday.
• A U.S. official called Secretary of State John Kerry's remarks in Britain on Monday a "major goof," saying Kerry "clearly went off script here." The official was referring to Kerry's assertion that al-Assad "could turn over every single bit of his chemical weapons" to avoid potential U.S. military action. "There is no one in the administration who is taking this Syria proposal seriously," the official said.
• Al-Assad "could turn over every single bit of his chemical weapons to the international community in the next week," Kerry said during a news conference with British Foreign Secretary William Hague, before Moallem's statement. "But he isn't about to do it, and it can't be done, obviously."
• Al-Assad told CBS's Charlie Rose that "you should expect everything" if there's an attack. "The government's not the only player in this region. You have different parties, different factions, different ideologies. You have everything in this decision now," he said.
• Lavrov called for international talks in Moscow to promote a peace process for Syria and avert an American military strike. He blamed U.S.-backed rebels in Syria for preventing a peace conference in Geneva, Switzerland.
• Kerry said it is al-Assad who will not negotiate as long as he is not prevented from using chemical weapons. Despite American support for militarily targeting the regime's ability to use chemical weapons, Kerry said, "The end to the conflict in Syria requires a political solution. There is no military solution."
• Moallem said his government questioned "the aim of this aggression that seeks to degrade the capability of the Syrian army in favor of al Qaeda and its affiliates."
• British Foreign Secretary William Hague said his country and the United States are aligned in four areas: creating conditions for a Geneva peace process, addressing the humanitarian tragedy, supporting the moderate Syrian opposition and "mustering a strong international response to the use of chemical weapons."
• U.N. Secretary-General Ban Ki-moon said Monday that he is considering urging the Security Council to demand the Syrian government immediately hand over its chemical weapons to be destroyed.
• A top Obama administration official says he believes that the congressional votes favoring a military strike against Syria will be there "at the end of the day." The goal of a strike would be to "deter" and "degrade" al-Assad's "ability to use chemical weapons," Deputy National Security Adviser Ben Rhodes told CNN's "New Day."
• The Syrian president and his regime used chemical weapons, Rhodes argued. "No doubt in our mind," he said. "We're going to show Bashar al-Assad there are consequences for the use of these weapons."
American public opinion
• A CNN/ORC International poll shows that even though eight in 10 Americans believe that the al-Assad regime gassed its own people, a strong majority doesn't want Congress to pass a resolution authorizing a military strike against it.
• More than seven in 10 say that such a strike would not achieve significant goals for the U.S., and a similar amount say it's not in the national interest for the U.S. to get involved in Syria's bloody two-year-long civil war, the poll says.
• The House and Senate are in session at 2 p.m. Senate Majority Leader Harry Reid is expected to take the first procedural steps to overcome an anticipated filibuster over whether to officially take up the Syria resolution.
• Obama will give a preview of his address to the nation when he does a round of interviews with major TV and cable outlets. CNN's Wolf Blitzer will report on his interview with the president on "The Situation Room."
• All House members get an intelligence briefing from Kerry, Secretary of Defense Chuck Hagel, National Security Adviser Susan Rice, Joint Chiefs Chairman Martin Dempsey and Director of National Intelligence James Clapper. Rice will also brief members of the Congressional Black Caucus.
• Rep. Mike Rogers, chairman of the House Select Committee on Intelligence, said he understands the citizenry's skepticism over military action and said it would be a "horrible mistake" to move ahead without winning '"enough votes" and "confidence" in Congress.
• Rogers said chemical weapons pose a "serious problem" and pointed to "national security consequences for the United States." He said Congress needs to focus on the "consequences of doing something and the consequences of not doing something."
"What I hope happens this week is we have that dialogue, that discussion and that debate as we should as members of Congress about national security issues."
• Sen. John McCain criticized Kerry's comment that a Syria strike would be "unbelievably small." In a Twitter message, McCain called the comment "unbelievably unhelpful."
He was referring to Kerry saying, "We're not going to war. We will not have people at risk in that way. We will be able to hold Bashar al-Assad accountable without engaging and troops on the ground or any other prolonged kind of effort, in a very limited, very targeted, very short-term effort that degrades his capacity to deliver chemical weapons without assuming responsibility for Syria's civil war. ... That is exactly what we're talking about doing. Unbelievably small, limited kind of effort."
CNN's Joe Sterling contributed to this report.