LONDON (Reuters) - A British Airways plane crash at London's Heathrow airport in January was likely caused by ice in the jet's fuel system, a report into the incident said on Thursday.

The accident, which seriously injured one passenger when the plane landed 1,000 feet short of its intended runway, was not the fault of the flight crew, the Air Accidents Investigation Branch (AAIB) said in an interim report into the incident.

It also ruled out problems with the amount or quality of the fuel, focusing instead on the build-up of ice in the system. The Boeing Co 777-200 ER aircraft, which used engines from Rolls Royce, had flown into London's Heathrow airport from Beijing.

"There are no safety recommendations specific to British Airways. We will work closely with the relevant regulatory authorities and comply with any requirements issued to all operators (of the aircraft)," the British carrier said in a statement.

However, Boeing recommended all 11 airlines globally that fly 777s with Roll Royce engines, including American Airlines, a unit of AMR Corp, and Delta Air Lines Inc, to take steps designed to minimize chances of ice buildup.

More than 220 planes are included in the Boeing advisory.

The primary recommendation is for pilots to increase engine thrust periodically when fuel temperatures drop below a certain level to force out any accumulated ice.

U.S. aviation regulators are expected to make the remedy mandatory in the coming days.

British Airways shares were down 4 percent at 251 pence by 1504 GMT, hit by the weak pound and the rising price of oil.

The AAIB report said the incident was unique and the investigation would continue.

"Extensive data analysis has revealed that not only has there never been a previous occurrence of this type on the Boeing 777, but also that this is the first known occurrence of this nature in any large modern transport aircraft," it said.

(Reporting by John Bowker and John Crawley in Washington; Editing by Elaine Hardcastle and Xavier Briand)