PARIS (Reuters) - The French government is willing to take a stake of 10 percent or more in Alstom (>> ALSTOM) alongside Mitsubishi Heavy Industries (MHI) (>> Mitsubishi Heavy Industries, Ltd.) as part of the Japanese firm's joint offer with Siemens (>> Siemens AG), an Alstom union representative told Reuters on Tuesday.

MHI Chief Executive Shunichi Miyanaga told French lawmakers earlier that he "strongly" wished that the French state would take an equal 10 percent holding to the one MHI offered to buy from Alstom's top shareholder Bouygues (>> BOUYGUES) to demonstrate that the engineering group would remain French.

The union representative, who was attending a briefing with French Economy Minister Arnaud Montebourg on Tuesday, said the government was looking to buy the stake in Alstom via state bank BPI.

A spokesman for Bouygues said earlier it had been contacted by MHI about a purchase of its stake, but had not yet been approached by the French government or the BPI.

(Reporting by Natalie Huet; Editing by James Regan)