The Border Force has to get non-EU passport holders through immigration at Heathrow within 45 minutes for 95 per cent of the time. However, it failed to meet that target at three of the four terminals in June at the west London airport, which this month will handle thousands of Olympics-bound passengers.
The EU passport holder target, in which queues must be no longer than 25 minutes for 95 per cent of the time, was reached at all four terminals.
A BAA spokeswoman said: “Long immigration queues are unacceptable. Passengers arriving at Heathrow deserve a good experience and a great welcome.”