Aviation authorities in the US and Europe are to order airlines flying Rolls-Royce-powered 777s to change operating procedures after a British Airways jet crash at London Heathrow airport in January.

The seven-month probe by air accident investigators has shown that the fuel flow to both engines on the BA 777-200ER was restricted – most probably due to ice within the fuel system, according to an interim report published on Thursday by the Air Accidents Investigation Branch of the UK transport department.