Government delays have cost the passengers stranded at Heathrow the chance of compensation, the Liberal Democrats have claimed.

The 80,000 travellers currently stuck as the result of a walkout by check-in staff would have been entitled to compensation had a new EU law passed last month been in place, the party claimed on Thursday.

The Single European Sky compensation rules state air passengers should be offered free meals, refreshments or hotel accommodation when an airline has to delay a flight significantly.

The party calculated the bill for passengers spending a night in a hotel would have cost British Airways around £4 million.

The Liberal Democrats also released figures showing that average delays at Britain's seven busiest airports have increased by six per cent since 1997.

"Alistair Darling must act swiftly to ensure this new law is implemented so that people get compensated for this sort of holiday farce," said transport spokesman Don Foster.

"With delays up by six per cent, most people will have endured the crowded departure lounges and interminable waits that thousands of families have experienced over the last few days. Thousands of holidays are literally being 'lost' every year in the departure lounge."