The US envoy to the UN warned that a monitor mission could be curtailed, while rebel fighters amassed weapons in preparation for a renewal of fighting.
Although the Syrian regime flouted a deadline earlier this week, it seems to be abiding by the UN cease-fire that went into effect today.
Saudi Arabia and other Gulf nations are setting up a fund to pay members of the Free Syrian Army as part of a larger international commitment.
The day after Syrian President Bashar al-Assad reportedly agreed to UN envoy Kofi Annan's cease-fire plan, fighting continued in several cities.
The embassy closure by such a key regional player is likely to increase pressure on the Syrian government. Turkey also pledged, along with the US, to increase 'non-lethal aid' to Syrian rebels.
The United Nations Security Council secured Russia's critical backing yesterday for a statement backing envoy Kofi Annan's peacemaking plan. The step marks a distinct shift in Russia's stance.
Syrian government troops and rebel forces clashed in the most violence Damascus has seen in the year-old uprising.
After overrunning Homs and launching an assault on Idlib, Syrian government troops are staging an offensive on Deraa, where the uprising began a year ago.