The battle for Alstom's prized energy business heated up on Wednesday,as the board of the French "national jewel" said it favoured an offer by US giantGeneral Electric while Germany's Siemens upped its rival bid. The US and German behemoths have been publicly vying for Alstom's energy assetsfor days in a politically sensitive battle over the French group.France's government, which views Alstom as a firm of national strategic importance,has waded into the bidding war, with Economy Minister Arnaud Montebourg vowingto defend the "industrial interests of the nation".In a statement, Alstom said on Wednesday that its board, which met the previous evening, was in favour of GE's 12.4-billion-euro ($17-billion) bid for its energy arm,without closing the door to other proposals.It said it acknowledged "unanimously the strategic and industrial merits of this (GE)offer" and had decided to set up a committee to review the bid in depth by the endof May."It has however reserved the right to respond to unsolicited offers for its entireenergy business and engage in discussions with bidders demonstrating a seriousinterest that could lead to a superior offer for Alstom," the group added.News the company could fall into American hands has angered some in France,including firebrand Economy Minister Arnaud Montebourg. "It's not over yet," Montebourg said on Wednesday."We have a few weeks ahead of us ... and the government intends to use this time todefend the industrial interests of the nation."French Prime Minister Manuel Valls took a more conciliatory tone, telling FranceInter radio that the view of the government had been taken into account over the future of what he has described as a company "of national strategic importance".In a bid to further reassure the government, Kron said on Wednesday the statewould "have a say" on the outcome of negotiations over Alstom's energy assets.Energy activities -- which include power generation and transmission -- account forabout 70 percent of Alstom's business but the company is better known as a railwayequipment maker that manufactures France's prized TGV high-speed trains.- Keeping jobs a priority French President Francois Hollande, who met the heads of GE and Siemens onMonday, is concerned mainly with safeguarding jobs at Alstom as his Socialistgovernment battles record unemployment and declining industrial competitiveness.The French firm is one of the country's biggest private sector employers with about18,000 staff nationwide.Christian Noyer, governor of the Bank of France, said the case "highlights that someFrench companies struggle to survive alone, and there again you have a problem ofcompetitiveness.""It's one more argument showing that increasing the competitiveness of French companies is essential," he told Europe 1 radio.During his hour-long meeting with GE's chief executive Jeffrey Immelt, Hollandepressed his case for jobs and for Alstom's French decision-making centre to beprotected. GE in turn addressed this concern in a letter to the French presidency, stressing itsdesire to create a "world leader in energy in France" and generate jobs in thecountry.Siemens, meanwhile, values Alstom's energy business at 10.5 billion to 11 billioneuros, and has offered to hand over part of its trains business to the Frenchcompany in the deal. In a letter from the German engineering giant to Alstom seen by AFP Wednesday, thecompany upped the transport part of the bid to include its underground trainsbusiness as well as the high-speed trains sector.Siemens is also holding discussions with Rolls Royce to buy its gas turbine andcompressor business, a Siemens spokesman said Wednesday, adding that the  firm'ssupervisory board will discuss the matter on May 6.A source close to the matter told AFP that the division was worth about £900 million($1.5 billion, 1.1 billion euros).The entire division has an annual turnover of £1.538 billion.