Earlier, Gatwick said it was "running well" and had made significant progress rectifying a technical issue which caused delays on Saturday.

But Elaine MacDonald, travelling on Sunday, described "absolute chaos" after queuing for about 90 minutes.

Gatwick said it had seen "some queuing" but overall it was "running as usual".

Another traveller, Sarah Mo from London, said she had been stuck at check-in for an hour and none of the bag drop machines were working.

Ms Mo, was was catching a British Airways (BA) flight to Malta, said there were "hundreds of people getting really stressed about missing their flights".

Meanwhile, Patricia González Muñiz, from Bedfordshire, said when she arrived for her BA flight from Gatwick to New York, the queue was "out of the door".

She said despite waiting for about an hour and a half, she estimated there were "about 50" people still in front of her.

In a statement issued on Sunday morning, the airport said it had been working with the supplier to rectify the technical issue and significant progress had been made to fix it.

A Gatwick spokeswoman said: "The airport operation is running well this morning and passengers should plan their journey as usual.

"For any queries please contact your airline. There may be some delays due to air traffic control strikes in France."

Earlier on Sunday, the airport had indicated in a tweet that the technical issue was ongoing and had warned that passengers could still experience delays.