A ceasefire is now in effect in Syria amid continuing doubts by Western nations over whether the fighting will in fact stop.
The government said it would abide by the truce proposed by United Nations-Arab League envoy Kofi Annan, but respond to what it called attacks by armed terrorist groups.
The deadline set by Mr Annan for the truce to come into effect at 6am on Thursday (local time) came and went without any immediate reports of violence, but it will be some time before it is evident whether the ceasefire really has taken hold throughout the country, the BBC reports.
There is widespread scepticism among Western powers and the Syrian opposition about the chances of President Bashar al-Assad's regime really abiding by the truce.
If it does hold, the focus will fall immediately on the issue of the withdrawal of government troops, tanks and heavy weaponry - a step that was supposed to have been completed on Tuesday.
The United States said Syria's pledge to abide by the peace plan had "little if any credibility".
Its ambassador to the UN, Susan Rice, says Syria's the promise falls short of full compliance of the six-point peace plan and the condition put on the deal by Mr Assad shows it can't be trusted.
British Foreign Secretary William Hague said that if there was a ceasefire, the United Kingdom would work at the UN to send monitors to Syria urgently "to make sure they can't slide back to renewed conflict".
Following a phone call between German Chancellor Angela Merkel and US President Barack Obama, the leaders said they "shared the concern that the Assad government was not complying with the terms of the agreement negotiated by Kofi Annan".
But Russia - one of Syria's closest allies - said the rebels must respond with their own ceasefire.
Kofi Annan is due to brief the UN Security Council later on Thursday.
Meanwhile, the violence continued on Wednesday, especially in the city of Homs, the BBC reports.
Activists said at least 30 people were killed in offensives around the country, including the north and north-west, a valley west of Damascus, and in the south, near Deraa.
A spokesman for the main rebel force, the Free Syrian Army (FSA), said the ceasefire was unlikely to take effect because neither side would stop shooting.
The UN estimates about 9000 people have died since anti-government protests began in March last year. In February this year, the Syrian government put the death toll at 3838 - 2493 civilians and 1345 security forces personnel.