The U.S. Treasury Department is interviewing Wall Street bankers to advise the government on an initial public offering of General Motors Co , the Wall Street Journal reported on Saturday.

Among the firms competing for the advisory role are Greenhill & Co, Lazard Ltd and Perella Weinberg Partners, the newspaper said, citing people familiar with the meetings.

Treasury officials could not be reached, but declined to comment for the Journal report. GM declined to comment.

GM, the No. 1 U.S. automaker, emerged from a government-sponsored bankruptcy last July. GM received a $50 billion government bailout that gave the U.S. Treasury nearly 61 percent ownership of the company. Canada and the province of Ontario own nearly 12 percent.

Chief Executive Ed Whitacre said last month after meeting with Treasury Secretary Timothy Geithner and House of Representatives Speaker Nancy Pelosi that an IPO was a real possibility later this year or in 2011.

However, Whitacre previously had backed away from a 2010 timeline that his predecessor Fritz Henderson had laid out.

GM reports first-quarter results on Monday and executives have said privately that earnings will be very strong, including an operating profit.

The Journal said while an IPO is still several months away at the earliest the presentations by the investment banks were held this past week.

Before the bankruptcy filing, GM shares had traded on the New York Stock Exchange.

The newspaper said it was not clear whether Lazard's previous work during GM's bankruptcy for the United Auto Workers union that represents many hourly workers at the automaker would pose enough of a conflict of interest to steer Treasury away from the firm.

GM last month announced it had fully repaid the balance on more than $8 billion in U.S. and Canadian government loans extended as part of its bankruptcy last year.

Top White House economic adviser Lawrence Summers said last month that GM's better-than-expected progress has improved chances the U.S. government will sell its stake sooner than expected.

A government report said the overall bailout investment in GM will likely result in some loss, but the Treasury Department expects the shortfall to be much lower than forecast last year.

In addition to the nearly $7 billion in direct loans to GM, the U.S. Treasury extended $43 billion in bailout cash in 2009 -- for a total $50 billion investment.

The potential loss on paper to taxpayers on GM alone was once thought to be as high as $30 billion, according to the White House budget office. The projected shortfall is now under $8 billion, according to market calculations.

Whitacre said last month he was optimistic the taxpayers would get all of their money back.

The repaying of the GM loans and the completion in April of full accounting for its results since its emergence from bankruptcy in July 2009 were two key steps GM needed to make toward launching an IPO.

(Reporting by Ben Klayman; Editing by Will Dunham)