Paris - With threatened strikes against Syria on hold, the world was waiting on Wednesday for President Bashar Assad to act on a pledge to give up his regime's chemical weapons.
France and the United States warned that they will go back to military options if Syria is seen to be stalling.
With the risk of an attack having receded considerably for now, Assad - who turned 48 on Wednesday - was free to pursue his battle with a rebel coalition that has been left dismayed by the West's retreating from intervention.
President Barack Obama has asked US lawmakers to delay a vote on whether to authorise strikes to allow Russian-led attempts to broker a handover of Syria's chemical weapons arsenal time to bear fruit.
Obama is liaising closely with Russian President Vladimir Putin and Secretary of State John Kerry is to hold talks on the weapons initiative with his Russian counterpart, Sergei Lavrov, in Geneva on Thursday.
"It's too early to tell whether this offer will succeed, and any agreement must verify that the Assad regime keeps its commitments," Obama warned in an address to the nation from the White House on Tuesday evening.
"But this initiative has the potential to remove the threat of chemical weapons without the use of force, particularly because Russia is one of Assad's strongest allies."
The switch to diplomacy was welcomed on Wednesday by China, which also praised Syria's offer to sign an international treaty banning chemical weapons.
"We hope all relevant sides can grasp this opportunity to solve the Syria problem through diplomatic and political means," a foreign ministry spokesperson said.
France aligned itself with the US position, insisting that its forces would stay on standby while the diplomatic process is pursued.
"France will remain, in permanent contact with its partners, mobilised to punish the use of chemical weapons by the Syrian regime and to deter them from using them again," President Francois Hollande said after talks with his military chiefs.
Amongst Western leaders, Hollande has been the leading advocate of intervention in Syria, although, like Obama, he has been unable to convince a majority of his electorate of the case for action.
Obama said US cruise missile destroyers would remain in place within striking distance of Syria, warning that "the US military doesn't do pinpricks".
Israel's President Shimon Peres said on Wednesday he believed Obama would not back away from airstrikes if Syria is shown to be acting in bad faith.
"If there will be a crack in Syria's integrity I have no doubt that the US will act militarily," Peres said.
Syria was threatened with strikes in response to the use of sarin gas in a 21 August attack on rebel-held suburbs of Damascus. The US says the attack killed more than 1 400 people and was carried out by Assad's forces.
Obama said allowing a dictator to get away with such acts would threaten US security, but he assured his listeners that there would be no military action until UN inspectors had delivered a report into what happened.
Chemical weapons ban
Syria announced on Tuesday that it would join an international convention banning chemical weapons and hand over control of current stocks - effectively admitting for the first time that it has them.
Syria is one of only seven UN member states not already party to the 1993 "Convention on the Prohibition of the Development, Production, Stockpiling and Use of Chemical Weapons and on their Destruction."
Signatories are supposed to destroy any chemical weapons under their control and to allow UN inspectors access to their sites.
Russia has offered to oversee this process and has said talks with the Syrians on how to go about it are already under way.
The path to a peaceful resolution of the crisis remains littered with obstacles however with the US, France and Britain still at odds with the Russians over the next steps.
Putin says Syria cannot be expected to act with a gun to its head.
"It is difficult to constrain Syria or another country to disarm unilaterally while military action against that country is being prepared," the Russian leader said.
France and Britain are pushing for a UN Security Council resolution authorising military action in the event of Syria failing to act on its disarmament promises.
Russia has made it clear it will veto any ultimatum of that kind and is likely to be able to count on backing from China, a fellow permanent member of the Security Council.
Syrian opponents of the Assad regime have warned that the chemical weapons negotiations will do nothing to end a conflict in which over 110 000 people have died in more than two years of fighting.
UN human rights investigators on Wednesday reported that the conflict had been characterised by widespread war crimes, mostly but not all committed by regime forces.
The team was unable to reach any conclusions on the use of chemical weapons, which is being investigated by a different group of experts.
The image of Assad's opponents in Syria meanwhile suffered a blow with reports emerging of an incident in which one Christian resident of Maalula had been forced to convert to Islam at gunpoint after the ancient town was overrun by Islamist fighters last week.
The Islamist wing of the opposition was also blamed for the apparently sectarian killing of 12 civilians from the minority Alawite community - to which Assad belongs - during attacks on villages near Homs on Tuesday.