Two US officials say the United Arab Emirates, a key Arab member of the US-led coalition against the Islamic State of Iraq and the Levant (ISIL), had stopped flying combat missions over Syria since December after the capture of a Jordanian pilot.

The Gulf Arab state dropped out of the group of countries conducting air strikes against ISIL targets in Syria, citing fears for their pilot's safety in the case of downed planes, the officials said.

A video of Moaz al-Kassasbeh being burned to death by ISIL surfaced on Tuesday nearly a month after his plane was shot down over Syria.

The US officials spoke on Wednesday only on condition of anonymity because the move has not been announced and they were not authorised to speak on the record.

The New York Times was the first to report the news of the UAE's decision to stop conducting air strikes.

The UAE has demanded that the US improve its search-and-rescue efforts, including the use of V-22 Osprey tilt-rotor aircraft, in northern Iraq, closer to the battleground, instead of basing the missions in Kuwait, the New York Times cited officials as saying.

The country's pilots will not rejoin the fight until the Ospreys, which take off and land like helicopters but fly like planes, are put in place in northern Iraq, the report added.

Even after the UAE stopped flying the missions, the US military has continued to state in daily news releases about the air campaign that the UAE is among coalition partner nations "conducting air strikes in Syria".
(Al Jazeera)