Nato has so far refused to be drawn into the conflict in Syria – where a US-led coalition is targeting Islamic State strongholds – due in part to concerns by alliance members like Germany that its involvement could complicate peace negotiations.

The US request for Nato to contribute its Awacs (Airborne Early Warning and Control System) surveillance planes was made in December.

The Awacs – which can locate and identify planes more than 400km – could act as flying command posts, communicating with other aircraft and helping to co-ordinate coalition airstrikes against ISIS.

The US-coalition involves about 60 countries, including all 28 Nato members and regional players such as Saudi Arabia and Egypt.

Nato’s fleet of 16 Awacs is based in Geilenkirchen, near the western German city of Aachen. The planes, which are specially adapted Boeing 707s, tend to fly with a 16-strong crew of international experts, including computer and radar specialists.

The planes are not equipped with weapons. The military personnel operating them come from 15 alliance countries, with the German army providing approximately one-third of the crew for the Awac fleet.

Nato decided several weeks ago to move some of its Awacs to Turkey, following a request by the government in Ankara. The alliance member said it felt threatened by the conflict in the region.

Turkey says that Russian planes deployed in Syria have entered its airspace on several occasions. In November, the Turkish air force downed a Russian military jet near its border with Syria, triggering a major diplomatic stand-off.