DETROIT  The Treasury Department has turned down a request by General Motors for up to $10 billion to help finance the automaker’s possible merger with Chrysler, according to people close to the discussions.

Instead of providing new assistance, the Treasury Department told G.M. on Friday, the Bush administration will now shift its focus to speeding up the $25 billion loan program for fuel-efficient vehicles approved by Congress in September and administered by the Energy Department.

Treasury officials were said to be reluctant to broaden the $700 billion financial rescue program to include industrial companies or to play a part in a G.M.-Chrysler merger that could cost tens of thousands of jobs.

But it remained unclear whether the officials were also seeking to avoid making any decision that would conflict with the goals of a new presidential administration. The Democratic candidate, Senator Barack Obama, has said in recent days that he supports increasing aid to the troubled auto companies, while Senator John McCain has not said whether he would support aid beyond the $25 billion.