JPMorgan Chase & Co. and Morgan Stanley, which led investment banks on General Motors Co.’s initial public offering, probably will handle the next sale of the automaker’s shares, said a person familiar with the matter.

The U.S. Treasury Department, the Detroit-based automaker’s biggest shareholder, won’t sell more shares until at least August to wait for the stock price to climb, two people familiar with the decision have said.

While the Treasury, which owns 33 percent of GM, can file for a secondary offering as soon as May 22 using the same form as for an IPO, which requires a lengthy regulatory review, reported Bloomberg. At Morgan Stanley’s suggestion, the department decided to wait until July 1, when it can file a simpler document and have more flexibility on timing, said the people.

“You need a megabank to underwrite a deal that is the size of what the U.S. Treasury will be selling,” said Peter Bible, GM’s former chief accounting officer who now heads the public companies group for New York-based accounting firm EisnerAmper LLP. “Those two make the most sense given their size. They did a tremendous job on the IPO.”

The U.S., which invested $49.5 billion in GM during its 2009 bankruptcy and restructuring, still is talking with other investment banks about underwriting roles, and a final decision won’t be made until closer to a stock sale, said the person, who asked not to be identified revealing private plans.

GM fell 35 cents to $31.07 at 4:15 p.m. in New York Stock Exchange composite trading.

Treasury officials put off deciding on the timing of a GM secondary offering because the stock has mostly traded below the $33 per-share IPO price. While the company beat earnings expectations on May 5, the stock fell 3.1 percent that day. The lower price affirmed the Treasury’s decision that it would be better to wait until the second-quarter profit is announced, the people said.

“The longer they wait, the better the return for the Treasury will be and for the taxpayer,” Dennis Virag, president of Automotive Consulting Group in Ann Arbor, Michigan, said in a telephone interview yesterday. “The auto market in the U.S. is recovering, and it’s a fairly consistent recovery.”

The Treasury doesn’t expect to sell its remaining 33 percent stake in a single secondary offering, one of the people said.

If Treasury opted to file an S-1 registration statement, the kind of document used for an IPO, the offering would have to go through a rigorous review that could last a month or longer, similar to an initial stock sale, Bible said in an interview today.

With the simpler S-3 filing, the SEC can review GM documents it already has, so the registration could be done in days, Bible said. That would allow the government to better time a sale to a higher price.

GM’s management and President Barack Obama’s administration want to end the almost two-year period of government ownership, the people said. The Treasury doesn’t expect to get the $44 average share price needed to break even on the $49.5 billion investment, they said. Further share sales need to average $53 a share to make up for the $33 per-share IPO price.

“We’re going to lose money in the auto industry on net, but we did this for the jobs we were going to save, not to maximize return,” Treasury Secretary Timothy F. Geithner said at a Detroit Economic Club event on April 28. “We’re not a private investor. Our job was to protect the country.”

The Treasury provided $85 billion of commitments to the auto industry, which included $64 billion to GM and Chrysler Group LLC, according to the Congressional Budget Office. The remaining assistance was provided to auto-parts suppliers and to finance arms Chrysler Financial Corp. and GMAC Inc., which is now known as Ally Financial Inc.

The Treasury aims to get at least the $33 IPO price and would prefer to sell shares in the high $30s or into the $40 range, where most analysts have set their target price, the people said. The department also wants to begin selling shares this year, they said.

GM raised more than $23 billion, mostly for U.S. and Canadian governments and a union health fund, selling common and preferred stock in its initial public offering in November. Bank of America Corp. and Citigroup Inc. were also listed among leaders of the investment banks.

The Treasury plans to wait for GM to announce a second- quarter profit before selling any more shares, which could be in August or September, or it may wait until November, after third- quarter results, the people said.

“What Treasury does with their GM shares is entirely up to them,” Jim Cain, a GM spokesman, said yesterday. “We’re focused on growing profitably around the world, further strengthening our balance sheet and fully funding our pension plan.”

Government ownership is weighing down GM shares, said David Whiston, an analyst with Chicago-based Morningstar Inc.

“A portfolio manager who believes the GM story may stay on the sidelines because when Treasury files to sell, the stock could sink,” he said in a telephone interview yesterday. “Other investors don’t want to invest simply because there is government ownership.”

Chief Executive Officer Dan Akerson bought $939,900 in shares of the automaker, GM disclosed today in a regulatory filing. The purchase of 30,000 shares at $31.33 apiece was a personal investment by Akerson, said Jim Cain, a GM spokesman.