DAMASCUS: Syria's army and main rebel force have announced they will cease fire, in line with an internationally backed truce during a Muslim holiday, but both have reserved the right to respond to any aggression.
A peace initiative by the United Nations and Arab League peace envoy Lakhdar Brahimi called for a truce during the four-day Muslim holiday of Eid al-Adha marking the end of the hajj pilgrimage.
The army announced it would adhere to the ceasefire in a statement read on television.
"On the occasion of Eid al-Adha, military operations will cease on Syrian territory as of Friday morning, until Monday the 29th," it said.
But it also said the army would react if "armed terrorist groups continue to fire on civilians and government troops, attack public and private property and use car bombs and improvised explosive devices".
It also warned of a response if rebels reinforce their current positions or receive ammunition, and to any fighters crossing from neighbouring countries.
The Free Syrian Army, chief among many rebel groups battling President Bashar al-Assad's forces, responded positively soon afterwards, saying it too would lay down its weapons as long as regime troops adhere to the ceasefire.
"We will respect the ceasefire from tomorrow morning if the Syrian army does the same," said General Mustafa al-Sheikh of the FSA, which had previously said it doubts Damascus would stand by any commitment.
"But if they fire a single shot, we will respond with 100. So we reserve the right to respond," he said by telephone from Turkey.
The ceasefire was backed this week by the UN Security Council, and a spokesman for UN chief Ban Ki-moon said "the world is now watching" to make sure both sides stuck by their commitment.
The United States expressed the hope both sides would respect the ceasefire.
"What we are hoping and expecting is that they will not just talk the talk of ceasefire, but that they will walk the walk, beginning with the regime," the US State Department spokeswoman, Victoria Nuland, said.
If they fire a single shot, we will respond with 100.
If the ceasefire holds, it would be the first real breakthrough in halting – even temporarily – the 19-month conflict that rights groups say has killed more than 35,000 people.
Mr Brahimi said he wanted the ceasefire to help create political space for dialogue and for aid to flow in, particularly to Aleppo, Homs in the centre and Idlib in the northwest.
And the UN's refugee agency said it was ready to send emergency aid to thousands of Syrian families in previously inaccessible areas if the ceasefire holds.
But on Thursday there were no signs of a slowdown in the fighting, with rebels moving into a strategically important Kurdish district of the main battleground city of Aleppo.
Residents of the Ashrafiyeh neighbourhood said about 200 rebels had entered the area for the first time.
One said the rebels, who arrived on vehicles mounted with heavy machine guns and bearing the markings of the Liwa al-Tawhid main rebel unit, made it clear they were settling in for Eid despite the ceasefire promises.