The chief executive of Ryanair Michael O'Leary said he did not expect to come under pressure from US shareholders to sell Ryanair's stake in Aer Lingus.

He was one of the largest shareholders in Ryanair and if other shareholders did not like what the company was doing, they could sell their Ryanair shares, said Mr O'Leary.

The Ryanair board remained happy with the company's €340 million investment in Aer Lingus, which was "not a lot of money", he told a press conference in Dublin yesterday.

Mr O'Leary said it was his view that Ryanair would continue to grow its operations out of Ireland and that Aer Lingus would suffer.

The bid for Aer Lingus had been "dead in the water" for the past four months but the company would nevertheless go to the European Court of First Instance to have yesterday's ruling by the European Commission overturned. "I think we have a very good chance of turning it over."

He said such a development would "get the regulatory issue out of the way" for any future bid for Aer Lingus which Ryanair might choose to make.

Mr O'Leary described yesterday's decision by the commission to prohibit Ryanair's merger with Aer Lingus as "stupid", "unlawful" and "clearly political". He said the views of the Irish Government had been been given precedence over the interests of the consumer.

The commission had no power to force Ryanair to sell its 25.2 per cent stake in Aer Lingus as Ryanair had no control over the former State airline, said Mr O'Leary.

He said the "real question now is, what happens to Aer Lingus?" It remained a small peripheral airline and Ryanair was "kicking the hell out of" it. The airline "will get in trouble again because of its cost base", he predicted. He said Ryanair's vision had been that Aer Lingus would have been a lot better off owned by Ryanair. Mr O'Leary said the Aer Lingus pilots who bought shares in the airline were "now nursing large losses. There's always a silver lining to every grey cloud."

A spokesman for the Competition Authority said it had no power to force Ryanair to sell its stake in Aer Lingus.