Heathrow Terminal 5’s disastrous opening was partly caused by delays in the building programme, according to Willie Walsh, British Airways’ chief executive.

Walsh told MPs at a transport select committee hearing last week that continuing building work meant his staff had been unable to train properly before the airport’s opening on 27 March.

He said: “The building programme was not 100% complete … I regret the fact that we allowed that to compromise our testing.”

Colin Matthews, chief executive of BAA, admitted at the same hearing that 28 of the terminal’s 275 lifts were not operational on its first day of opening.