(Adds fresh minister comments on Siemens)
By Natalie Huet
PARIS May 14 (Reuters) - France's energy minister muddied the waters over the future of engineering group Alstom on Wednesday, eventually toeing the government line on the need to examine a proposal from Siemens after first appearing to favour a tie-up with General Electric.
In a magazine interview in which she also called her male colleagues "cocksure machos", former presidential candidate Segolene Royal said: "General Electric is a very good opportunity for Alstom. It's the best industrial project.
"Why not say it? ... And why do we always try to scare away foreign investment? We actually really need it."
Cash-strapped Alstom has welcomed GE's offer to buy its power turbines and grid business for 12.35 billion euros ($16.9 billion), but the French government has weighed into the talks in an attempt to get alternative offers.
Economy Minister Arnaud Montebourg has openly criticized the Alstom-GE deal and instead advocated a European tie-up with Germany's Siemens. Alstom has given itself until the end of the month to review its options.
Royal changed tack later on Wednesday, saying she had no preference at this stage.
Siemens "has considerably improved its offer" to include a "European project" in the areas of trains and renewable energy, she said after a meeting between French ministers and Siemens CEO Joe Kaeser in Paris.
"The different offers will be compared with each other, and these offers are in the process of improving, it's a good thing for jobs in France," she added.
A source familiar with the matter said Kaeser did not bring any concessions to the table during Wednesday's talks.
The outspoken Royal, who is also the mother of President Francois Hollande's four children, said in the Paris Match magazine interview that her male colleagues treated her with contempt.
Angry with the resurgence in parliament of an environment tax she wants to bury, Royal, who made a political comeback when she was named minister in March, told the magazine she would not be silenced.
"If they think they can muzzle me, they're mistaken," she said. "Yes, I do speak my mind. This is my right and I will defend it whatever happens."
For its part, GE has entered talks to sell minority stakes in Alstom's wind and hydroelectric businesses, said a source close to the talks on Wednesday.
When detailing GE's bid, CEO Jeff Immelt had signaled in a letter to Hollande that the U.S. group was willing to work with the government and to sell Alstom's wind turbine activities to French investors. Areva has been cited in newspaper reports as a likely buyer but has declined to comment.
A spokesman for GE France declined to comment on Royal's comments. Alstom declined to comment beyond saying the committee of independent directors it had set up to review the GE bid was at work and that Siemens had still not made a formal offer. Siemens also declined to comment. ($1 = 0.7296 Euros) (Additional reporting by Jens Hack in Munich; Editing by Andrew Callus and James Regan)