Cross-channel concern over beleaguered industrial giant Alstom has resulted in worries over hundreds of jobs in Hampshire and troubled times at the French shipyard constructing Southampton megaliner Queen Mary 2.

Ailing Alstom, parent company of Chantiers de l'Atlantique, the shipyard now nearing completion of Cunard's massive 150,000-ton transatlantic liner, may have been bailed out by a last-minute £2 billion refinancing deal from the French government and more than 30 banks but worries still remain for the engineering and shipbuilding empire.

Struggling with a mountain of debt, Alstom has confirmed plans to halve its 10,000-strong workforce across the UK, raising fears that jobs could be at risk at Eastleigh's railway works where more than 500 people are employed.

An Alstom spokesman said jobs would be going in Birmingham, Stafford, Rugby and Kidsgrove, leaving another 500 jobs which could be affected by "some further restructuring'' in its other UK businesses but refused to give further details.

In France, at Alstom's Chantiers de l'Atlantique shipyard in Saint Nazaire, where QM2 is taking shape as Cunard prepares for the ship's Southampton arrival in December, there was relief at news of the financial reprieve for the company that is such a strong symbol of French national pride.

However, it was not long before another dark cloud was hanging over the Brittany yard in the shape of a $300m lawsuit launched by shipping line Celebrity Cruises against Alstom, together with Rolls-Royce, over the Mermaid pod propulsion system fitted to four of the company's cruise vessels, all built by Chantiers de l'Atlantique.

Celebrity Cruises said it was taking the action to recover what the company claims to be lost revenue and costs as a result of problems with the propulsion system forcing cancelled voyages.

Mermaid pods have also been fitted to QM2, although the configuration is different from the earlier system.