The United Nations yesterday suspended operations in embattled Syria and began withdrawing non-essential staff as the brutal civil conflict raged and the regime of Syrian President Bashar al-Assad was prompted to vow it would never use chemical weapons against its own people.

UN spokesman Martin Nesirky told reporters the organisation was suspending its missions in Syria indefinitely, amid fresh bloodshed in the war that has already claimed some 41,000 lives since it started in March 2011.

The UN pullout coincided with the US voicing concerns that Assad’s forces might be weighing up the use of chemical weapons.

US media reports earlier said the Syrian military had been detected moving the weapons around, and US Secretary of State Hillary Clinton warned yesterday their deployment would cross a “red line”.

“We are concerned that an increasingly beleaguered regime... may be considering the use of chemical weapons against the Syrian people,” White House spokesman Jay Carney added.

A Syrian foreign ministry official said Syria would “never, under any circumstances, use chemical weapons against its own people, if such weapons exist”.

The latest developments at the UN came after Russian President Vladimir Putin warned Turkey that the Nato deployment of Patriot missiles along its border with Syria could exacerbate tensions.

He met Turkish Prime Minister Recep Tayyip Erdogan in an Istanbul summit that failed to yield a common response to Syria’s conflict.

Russia vehemently objects to Turkey’s Nato request for the deployment of Patriot missiles as Assad’s regime clings to power and suppresses the rebellion.

Moscow has warned that such a deployment could spark a broader conflict pulling in the Western military alliance.

Putin underscored the point yesterday, the eve of a Nato meeting in Brussels that is expected to decide on Ankara’s request.