Alstom is a major player in the train-making industry

The sale to French nuclear power group Areva for �657.5m, was described by the company as "another key step" in a recovery plan aimed at cutting group debt of about �3.4bn.

The profitable division makes equipment for power generators and distributors and employs 25,000 people, of whom about 3,500 work in the UK.

Neither company has commented on the implications the transfer has for jobs.

Alstom chief executive Patrick Kron said he believed the division had a "bright future in the Areva group".

Rescue package

The division owns sites at Stafford, Rugby and Kidsgrove, near Stoke, and has sales of �2.2bn, accounting for 15% of Alstom's revenues.

Workers at Alstom in Birmingham protest at its closure

Earlier this week, Alstom got the go-ahead from the European Commission for a package to rescue the embattled company.

Alstom builds ships, power turbines and trains, including the French high-speed TGV and Virgin's Pendolino tilting trains.

The company has already announced plans to end production at its Birmingham train-making plant when the site completes its single remaining order for Virgin Pendolinos next year.

About 1,000 jobs will go as the plant at Washwood Heath switches to refurbishing trains.

A further 500 staff within the company's UK workforce could be affected by "some further restructuring" of its remaining UK businesses.

The moves are part of the company's plans to halve its 10,000-strong UK workforce within the next two years as it turns its British operations into a non-exporting service business.