Syrian rebels
A file photo of members of the Free Syrian Army taking up position with their weapons during clashes with forces loyal to Syria's President Bashar al-Assad, in the old city of Aleppo - Reuters

The CIA is working hand-in-hand with America's Middle East allies to ramp up the supply of weapons to Syrian rebels, according to a new report.

According to the New York Times, the CIA has facilitated a huge increase in arms airlifts from Saudi Arabia, Qatar, Jordan and Turkey to the rebels fighting Syrian President Bashar-al-Bassad.

It is claimed that, "from offices at secret locations", American intelligence staff are working hand-in-hand with the Middle Eastern governments to buy the arms, and vet rebel commanders to determine who is given access to the weapons upon their arrival.

The article cites Hugh Griffiths, of the Stockholm International Peace Research Institute (Sipri), who says that by "a conservative estimate", 3,500 tonnes of military equipment have been airlifted since early 2012.

"The intensity and frequency of these flights" are "suggestive of a well-planned and coordinated clandestine military logistics operation," Griffiths added.

The airlift operation, which began with only a trickle of furtive deliveries, has reportedly grown to encompass more than 160 flights, delivered by cargo planes from Jordan, Qatar and Saudi Arabia. The planes are using Ankara's Esenboga Airport as a principal terminus.

The report claims to have consulted air traffic data, gleaned accounts from rebel commanders and interviewed officials in a number of countries.

A White House spokesperson denied to comment on the report, although he admitted he was aware of it. Meanwhile Turkey, which is reportedly co-ordinating the entire operation, has distanced itself from the New York Times claims.

"We don't have any official documents in hand that would confirm such reports," Turkish Foreign Ministry spokesperson Levent Gumrukcu told Today's Zaman.

While Saudi officials remain tight-lipped, Jordanian officials have denied the claim.

"This is all lies. We never did any such thing," said Muhammad Jubour, cargo director of Jordanian International Air Cargo.

In a separate development, the UN has decided to pull out half of its international staff from Syria.

"The United Nations Security Management Team has assessed the situation and decided to temporarily reduce the presence of international staff in Damascus due to security conditions. The United Nations remains active and committed to helping the Syrian sides in their search for a political solution. UN agencies and their partners also remain committed to providing assistance to millions of people in need in Syria," said UN spokesperson Martin Nesirky.