AER LINGUS will this week drastically revise its 2009 trading forecasts as part of its defence against a hostile bid from Ryanair. It will say it could return to profit next year, or break even, rather than lose €20m (£18.6m).

The new figures are expected as part of the airline’s formal defence document against the €748m Ryanair bid. The revised forecast will surprise investors, who were told only weeks ago to expect a loss.

The announcement will be one of a number of bold measures contained in the company’s defence document aimed at strengthening its attempts to remain independent.

The airline is expected to announce it will restart flights between Shannon and Heathrow, which Aer Lingus controversially stopped in 2007. Aer Lingus was one of Shannon’s biggest customers and the Heathrow service one of the airport’s biggest. The decision caused the executive chairman of Shannon airport, Pat Shanahan, to resign. The move will be politically popular – the Irish government holds a 25% stake in the company.

Ryanair's hostile bid for Aer Lingus is worth about half what it offered in a failed takeover attempt in 2006 that was dismissed by the EU as anti-competitive. The latest bid has been dismissed as “ridiculously cheap” by the company's senior management.

Ryanair’s outspoken chief executive Michael O’Leary will have to raise his €748m offer substantially to have any chance of achieving a recommended bid from the board of Aer Lingus, led by chairman Colm Barrington. The company believes €2 billion is a more realistic value when its net cash, valuable Heathrow slots and brand name are taken into consideration.

On Friday, in a move to highlight its strength as an independent airline, Aer Lingus unveiled a £100m plan to open its first base outside Ireland at Gatwick airport, which would create 120 jobs in the first year. It will locate four Airbus A320s at Gatwick from next April, operating services to Malaga, Munich, Vienna, Nice, Dublin, Knock, Zurich and Faro, before expanding the base to eight aircraft within 12 months.

In a letter addressed to Barrington on Thursday, O’Leary said Ryanair “as a large shareholder” is concerned about some “apparently contradictory claims and forecasts” and their impact on Aer Lingus’s profit for 2008 and 2009.

In the final paragraph, O’Leary said: “As I’m sure you will appreciate, the above issues will be of utmost importance to all stakeholders in maximising shareholder value in Aer Lingus Group."

Earlier in the week, Barrington dismissed official offer documents posted by Ryanair to Aer Lingus shareholders as: “The usual stream of invective, spin and misrepresentation that we expect from the people at Ryanair.”

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