British Airways, Virgin Atlantic and airports operator BAA have told MPs they backed risk-based checks, but insisted security was paramount.
Corneel Koster, director of operations, safety and security at Virgin Atlantic, said: "We have a view that risk-based security can work. We think it's a direction that the UK Border Force can move in.
"It allows the Border Force to allocate resources to make sure security is as robust as possible and also efficient."
He also blamed the worsening queues on working patterns, staff cutbacks, a move away from the risk-based security regime and an increase in passenger numbers.
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Michael Fallon has received reassurances from his US counterpart that security ties with Britain will "endure" following a vote for Brexit.
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