By Arno Schuetze, Noah Barkin and Natalie Huet
FRANKFURT/BERLIN/PARIS (Reuters) - Germany's Siemens is working on a formal asset-swap offer for Alstom's power business that could come as early as this week and see France take a stake in a resulting rail-focused French group, sources close to the talks told Reuters.
Alstom is already in talks with U.S. conglomerate General Electric over a 12.35 billion euro ($16.9 billion) bid for its power arm, which it is due to review by June 2. However, under strong political pressure, it has opened its books to Siemens so it can propose its own deal if it wants to.
Some sources familiar with the talks cast doubt on whether Alstom would be interested in the new deal sketched out by Siemens. Still, a rival offer would give the French government more leverage with GE after it gave itself the power to block foreign takeovers in "strategic sectors".
The French government has repeatedly criticized GE's bid, favoring alliance between the companies rather than a straight sale of Alstom's power arm - which accounts for 70 percent of the group's revenue - that would leave the French group with just its smaller transport business.
Meanwhile it has advocated an alternative European tie-up between Alstom and Siemens. Initially though, it faced reluctance from both firms, long bitter rivals.
But after several trips to Paris by CEO Joe Kaeser and nearly two weeks of access to Alstom's data, Siemens has warmed to the idea and has been refining its bid to make it more attractive to Alstom and the French government, sources said.
"Siemens is presenting the following case: it will create national champions in trains and energy. Everything will be kept in Europe. It has offered some new elements, which sweeten its proposal," said a source familiar with the proposed deal.
In a short letter to Alstom late last month, Siemens had outlined a proposal worth $14.5 billion, offering to exchange part of its rail business plus cash in exchange for Alstom's power assets.
Two sources familiar with the talks said Siemens was now discussing handing over all of its rail business to Alstom and setting up a joint-venture in rail signaling.
To limit the German firm's influence in the resulting transport-focused Alstom group, Siemens is also discussing with Paris and Berlin the opportunity for France - which owns 0.9 percent of Alstom's capital via state fund CDC - to take a more sizeable stake, political and financial sources said.
One source said the French government could take a stake of over 10 percent in Alstom, as it seeks to secure the domestic roots of the engineering group which received a state bailout a decade ago and is a big private employer in the country.
On Friday, French Economy Minister Arnaud Montebourg said the government would not let domestic companies be "dismembered, chopped up into pieces and devoured" and did not rule out taking a stake in Alstom to help secure its future.
Meanwhile Siemens could offer to sell Alstom's wind and nuclear power assets to French state-controlled energy group Areva, thereby addressing government concerns over France's energy independence, said two sources familiar with the proposed deal.
As a further sweetener, Siemens is said to be offering to set up in France the headquarters of sub-units in Transmission and Distribution - the segment which makes gear to carry electricity from power plants to households - potentially strengthening the country as a hub for this technology.
Siemens declined to comment. It has previously said it plans to use the full four weeks allotted to it for due diligence, and then decide on whether to make a formal offer.
Alstom declined to comment beyond saying it was reviewing GE's bid and had received an expression of interest from Siemens, but no formal offer.
General Electric and Areva also declined to comment. Representatives for French state fund CDC could not be reached outside European business hours.
Kaeser, vaulted into the top job at Siemens nine months ago after his predecessor Peter Loescher was ousted in a boardroom coup, unveiled a restructuring earlier this month that puts a premium on profitability over growth.
As a result, he has seemed lukewarm about a tie-up with Alstom, saying at a recent strategy presentation in Berlin that his firm would not be forced into a bid.
But the new French decree, which gives the government formal powers to overrule foreign takeovers in "strategic" sectors from energy, water and transport, to telecoms and health, underscored for Siemens the lengths Paris is willing to go to pave the way for a European-only deal.
"Let's just say that the landscape seems to have shifted to our advantage," one official close to Siemens told Reuters.
However, sources close to Alstom say it wants cash and backs GE's bid, and while it does want to expand in rail signaling it is not interested in taking on more rolling stock.
Other impediments to a Siemens deal include antitrust concerns and opposition from unions. A German-French deal would imply more industrial overlap, raising the risk of job cuts and forced asset sales - especially in trains.
After competing aggressively for decades, Siemens and Alstom would also have a deep cultural divide to overcome.
Alstom CEO Patrick Kron has been referred to as a "Siemens hater" in the German press. Kron has rebuffed the tag, but industry sources say he has never forgiven the German group for lobbying against a state bailout for Alstom a decade ago in the hope of buying some of its assets.
Overall, GE remains ahead in the race for Alstom's assets, said one source close to the talks: "We are not at the stage where we are negotiating with Siemens a contract that could be signed tomorrow." ($1 = 0.7297 Euros)
(Additional reporting by Sophie Sassard in London, Markus Wacket in Berlin, Benjamin Mallet and Julien Ponthus in Paris; Writing by Natalie Huet and Noah Barkin; Editing by Elaine Hardcastle and Rosalind Russell)