Testy lawmakers pointed fingers at one another and President Barack Obama on Thursday as negotiations over raising the national debt limit entered a perilous endgame. Wall Street eyed the standoff with growing anxiety, warning of catastrophe if the U.S. defaults on its obligations.

With compromise talks at a vituperative standstill, Senate Republicans unexpectedly offered Tuesday to hand President Barack Obama new powers to avert the first-ever government default threatened for Aug. 2.

Beset by a weak jobs report, President Barack Obama on Friday called for swift action by Congress to raise the nation's borrowing limit, saying the uncertainty over the debt ceiling has hindered hiring in the private sector.

President Barack Obama declared a debt-crisis session Thursday with congressional leaders was "very constructive" but said the parties were still far apart on deficit reduction proposals. He said he would reconvene the negotiators on Sunday.

President Barack Obama is pressing Democrats to support a higher deficit reduction proposal that could win Republican support for new tax revenue while reducing costs for major benefit programs such as Medicare and Social Security as the price to reach a deal on raising the government's debt limit.

Senators to work next week on debt limit impasse