Syria crisis: US 'to drop military threat'
The US will drop its insistence that a UN resolution on Syria must be backed by military force, officials say, after strong objections from Russia.
US and Russian diplomats say the two sides are edging closer to a deal on Syria's chemical arsenal, as talks in Geneva entered a third day.
They are thrashing out the technical details of the disarmament process.
UN Secretary General Ban Ki-moon says a UN report will "overwhelmingly" confirm that poison gas was used last month.
He made no comment on who was to blame for the 21 August attack in eastern Damascus.
"We wouldn't be continuing if we didn't think there was room for progress," one US official in Geneva said. "But it's difficult."
The two sides "are coming closer on the size of the stockpile," a US administration official added. Going into these talks, the Americans and Russians cited very different figures for the size of the Syrian chemical weapons stockpile (an apparent 40% difference). The US has shared its intelligence on this with the Russians, which seems to have narrowed the difference.
The official would not be drawn on reports from Washington that the US no longer expects a UN Security Council resolution to include the potential use of military force. This, the official said, was not the focus of discussion in Geneva.
The stage would appear to be almost set for the announcement of a joint statement, probably on Saturday, that the US and Russia have reached agreement on the principles and framework of a plan to oversee the dismantling of Syria's chemical weapons.
But he said Syrian President Bashar al-Assad had committed "many crimes against humanity", in comments at the UN Women's International Forum that were shown on UN television.
The BBC's Nick Bryant in New York says Mr Ban appeared not to have realised his comments were being broadcast.
The US had threatened military action against Mr Assad's regime, accusing the military of killing more than 1,400 people in the 21 August attack.
But Mr Obama called off a Congress vote on the strikes after Russia announced a plan to place Syria's chemical weapons under international control and have them destroyed.
Syria has agreed to the plan and has sent documents to the UN to sign up to the Chemical Weapons Convention, which outlaws the production and use of the weapons.
US Secretary of State John Kerry is meeting his Russian counterpart Sergei Lavrov in Geneva to thrash out the technical details of seizing and destroying the chemical stockpile.
They reconvened on Saturday morning for a third day, with a US official telling journalists: "This morning's meeting has started."
Diplomats said some progress had been made on how to account for Syria's chemical weapons inventory, with the US and Russia narrowing their differences over estimates of the size of the stockpiles.
But a major point of contention between Washington and Moscow is reported to be the US insistence that any deal on chemical weapons be enshrined in a UN resolution, backed by the threat of military force for non-compliance.
Chemical weapons plan
5-6 Sep: Vladimir Putin and Barack Obama discuss placing Syria's chemical arsenal under international control on sidelines of G20 summit
9 Sep: Russia's Foreign Minister Sergei Lavrov urges Syria to hand in chemical weapons and have them destroyed; Syria welcomes plan
10 Sep: Syria's foreign minister makes first public admission of chemical stockpile; Syria commits to Russian plan. Mr Obama postpones Congress vote on military action
12 Sep: US Secretary of State John Kerry begins talks with Mr Lavrov in Geneva
The Russians had objected to any threat of force, and to any resolution that would blame the Assad regime for the Damascus poison-gas attack.
White House officials have now briefed reporters that the US is willing to drop its position on the use of force.
And the US side has now begun to talk only of unspecified consequences for non-compliance.
President Obama said earlier that "any agreement needs to be verifiable and enforceable".
The White House officials also said the US would reserve the right to take military action without UN backing.
Mr Lavrov said it was necessary "to design a road which would make sure that [the chemical weapons] issue is resolved quickly, professionally, as soon as is practical".
More than 100,000 people have died since the uprising against President Assad began in 2011. Millions of Syrians have been displaced.