Treasury Secretary Timothy Geithner says he's looked at all the options and that there's "no way to give Congress more time" to solve the debt limit problem.
Lawmakers face an Aug. 2 deadline to enact legislation to allow the government to continue to borrow to meet obligations like Social Security checks and payments to holders of U.S. Treasuries.
Geithner has employed several accounting moves to allow the government to avoid a first-ever default. He warns that a default would rock the credit and stock markets and would force up the interest the government has to pay on its bonds.
Top lawmakers return to the White House Thursday amid dwindling hopes for a bipartisan deal to slash the deficit and combine it with a debt limit increase.