The Republican-led House of Representatives and Democratic-led Senate pushed ahead yesterday with rival measures to avert a US default next week, but neither offered immediate hope for ending the political stand-off.

The top Republican in the House, Speaker John Boehner, hastily reworked his proposal to cut spending and raise the government’s borrowing authority after opposition from his party’s most conservative members forced him to postpone votes twice in two previous days.

The Bills could provide the basis for behind-the-scenes talks by congressional leaders aimed at finding a bipartisan compromise that could win approval in both chambers before Tuesday’s deadline.

If they fail, the government would run out of money after Tuesday. Lacking the authority to take on more debt, it would be unable to pay some of its obligations. A default would lower the US credit rating, which would have a ripple effect on the global economy and send interest rates soaring. Already, concerns about the impasse have sent world stock markets lower.

President Barack Obama declared today that “we’re almost out of time”.

“The power to solve this is in our hands on a day when we’ve been reminded how fragile the economy already is,” the President said from the White House, as US stocks fell in response to a sour report on economic growth and widespread uncertainty over the Washington debt stalemate. “This is one burden we can lift ourselves. We can end it with a simple vote.”

In the House, Republican leaders met behind closed doors with members in a last-ditch appeal. In the Senate, Mr Reid prepared for a showdown vote for tomorrow. He said he had invited Senate Republican Leader Mitch McConnell to join him in negotiations. “I know the Senate compromise Bill Democrats have offered is not perfect in Republicans’ eyes. Nor is it perfect for Democrats,” Mr Reid said. “But together, we must make it work for all of us. It is the only option.”

Mr McConnell dismissed the Democratic effort, arguing that it stands no chance in the Republican-controlled House, and he accused Mr Obama of pushing the nation to the brink of an economic abyss.

The revisions to the Republican House Bill would raise the nation’s debt limit by $900 billion ­ essential to allow the government to keep paying its bills ­ and cut spending by $917 billion, according to Republican David Dreier.

But a later increase in borrowing authority would not take effect unless Congress sent a constitutional balanced budget amendment to the states for ratification.