(Bloomberg News) T. Boone Pickens, who's been saying for more than a year that Congress was poised to pass his plan to subsidize natural-gas vehicles, may not have been expecting opposition led by fellow billionaire Charles Koch.

Pickens, 83, the chairman and chief executive officer of BP Capital LLC., a Dallas-based energy investment fund, has spent $82 million since July 2008 promoting the use of domestically produced natural gas to power cars and trucks, according to Jay Rosser, his spokesman.

Koch Industries Inc., Dow Chemical Co. and the American Conservative Union all have weighed in since May against a Pickens-backed bill that would provide tax breaks to purchase natural-gas fueled trucks. The critics say it would provide unwarranted subsidies to companies such as Clean Energy Fuels Corp., a Seal Beach, California, maker of natural-gas fueling stations in which Pickens is the biggest shareholder.

"We do not believe government should be picking 'winners and losers' in the marketplace," Phillip Ellender, president and chief operating officer for government and public affairs at Koch Companies Public Sector LLC, a subsidiary of Koch Industries, wrote in a June 23 letter to Congress.

Charles Koch, 75, is chairman and chief executive officer of Wichita, Kansas-based Koch Industries, which calls itself one of the world's largest closely held companies. He is also a co- founder of Americans for Prosperity, a group that says it advocates limited government and opposes the natural-gas legislation.

'Working for America'

"So here you are: Charles Koch working for Koch, Boone Pickens is working for America," Pickens said today in an interview on Bloomberg Television's "InBusiness With Margaret Brennan."

Koch's company imports crude oil, gains from ethanol subsidies and is in the fertilizer business, which benefits when natural gas is inexpensive, Pickens said.

"We oppose all government mandates and subsidies because they artificially skew economic signals about price and demand, thereby creating inefficiencies that divert resources from productive activities to politically favored ones," Ellender said in an e-mailed response to Pickens. "To add a new subsidy in these times of increasing unemployment and economic hardship for so many Americans is irresponsible and bad public policy."

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