U.S. President Barack Obama, his Democratic party allies in Congress and opposition Republicans are still haggling over competing plans to raise the government borrowing limit, as an August 2 deadline draws closer. Without an agreement, Washington could default on some of its obligations.

White House spokesman Jay Carney told reporters if the deadline is not met, the U.S. will lose its authority to borrow money for the first time. He said everyone involved in the negotiations is eager for a compromise in a way that will not prolong the uncertainty that has become a burden on the U.S. economy.

On Wednesday, some Republican lawmakers tried to rework a plan put forth by the speaker of the House of Representatives, John Boehner, after non-partisan congressional analysts said it would fall short on promised spending cuts.

Some members of the ultra-conservative Tea Party faction in Congress vowed to vote against the Boehner plan, or any proposal that would raise the $14.3 trillion debt ceiling.

A Democratic proposal crafted by Senate Majority Leader Harry Reid is also facing scrutiny. The non-partisan Congressional Budget Office says his plan to cut $2.7 trillion over 10 years overstates savings by half a trillion dollars. Some Republicans argue the promised spending cuts in Reid's proposal are not realistic.

Reid says Republicans should embrace his plan because it is a compromise that incorporates many spending cuts Republicans have supported, and does not include tax increases they strongly oppose.

The Congressional Budget Office said the plan put forward by Boehner cuts about one-third less than the $1.2 trillion Republican supporters said it would. Republicans have delayed a vote on the plan until at least Thursday as they revise it to make deeper cuts.

White House Chief of Staff William Daley says he is confident the United States will not default on its debt. He told television interviewers there are a lot of debt reduction plans on the table, and everyone is stressed as the August 2 deadline approaches. But he said, in the end, Congress will do what is right.

Uncertainty caused by the bitter partisan debate and the lack of apparent progress toward a compromise have worried investors. That is why many stock markets have declined, and the value of “safe-haven” investments like gold and the Swiss Franc have hit record highs against the U.S. dollar.