Airlines were warned to avoid flying over Crimea because of the airspace dispute that existed between Russian and Ukraine, it has been revealed.

The Federal Aviation Administration (FAA) took action in April to prohibit all US airlines from flying over Crimea because of the dispute between Ukraine and Russia about which country controlled the airspace in the Simferopol region covering the Crimea peninsula.

Initially concerns were raised over air traffic control rather than any military threat.

But because of the dispute, the International Civil Aviation Organization, a branch of the United Nations warned airlines on 3 April to avoid the area.

"In addition, political and military tension between Ukraine and the Russian Federation remains high, and compliance with air traffic control instructions issued by the authorities of one country could result in a civil aircraft being misidentified as a threat and intercepted or otherwise engaged by air defense forces of the other country," FAA said.

The Russian Federation declared March 28 that it controlled the airspace over Crimea, and international airspace above the Black Sea and Sea of Azov. Ukraine then created a prohibited area over the Crimean peninsula for flights below 29,000 feet.

Russian airline Aeroflot, Turkish airlines, Air France and British Airways have declared they will no longer be flying over Ukrainian airspace since the MH117 was shot down – killing more than 295 people on board.