Ryanair, the budget airline that was this week ordered to repay millions of pounds in subsidies, has suffered a further blow after it was criticised by the advertising watchdog for using offensive language and making false claims for its service.

The Advertising Standards Authority today banned a Ryanair campaign in which the airline had claimed it offered "the fewest cancellations" and "the best punctuality", adding: "Fly with Ryanair if you want to avoid... delayed flights, cancelled flights."

The ASA upheld complaints from six members of the public who said the advert was misleading, and ordered Ryanair not to repeat the claim.

The watchdog also banned a second newspaper campaign that appeared shortly before bonfire night and carried the headline "Fawking great offers!" surrounded by pictures of fireworks exploding.

Nearly 50 complaints were made from people who thought the headline was offensive.

Ryanair said the wording in the advert was "intended to be humorous" and did not believe it would cause widespread offence.

The Daily Telegraph, where the ad appeared, argued that because it ran shortly before November 5 their readership would understand "Fawking" was a light-hearted reference to a day of celebration.

But the ASA concluded the advert "was likely to cause serious or widespread offence to readers of the Daily Telegraph" and told Ryanair not to use the same approach again.

The European commission said this week that cut-price rates offered exclusively to Ryanair for using Charleroi Airport in southern Belgium were illegal.

But the airline will not have to repay all its subsidies from the Belgian regional government because some of the rebates for Ryanair were permissible as part of regional development support for the airport.

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