WASHINGTON -?US Treasury Secretary Timothy Geithner expressed confidence on Sunday that the US Congress will raise the nation's borrowing cap.

US Secretary of Treasury Timothy Geithner talks at the Senate Finance Committee on Capitol Hill in Washington, February 16, 2011. [Photo/Agencies]

"I want to make it perfectly clear that Congress will raise the debt ceiling," Geithner told the ABC television in an interview, adding that Republicans told this to President Barack Obama on Wednesday in the White House.

The world's largest economy is going to reach the current debt limit of US $14.3 trillion?no later than May 16 this year. Defaulting on legal obligations of the United States would trigger a financial crisis potentially more severe than the crisis from which the nation is only now starting to recover, Geithner said on April 4 in a letter to Congress.

The US public debt figures are closely watched globally at a time when increasingly more economists believe that the US soaring debt is unsustainable. The combined US federal public debt surpassed 14.1 trillion dollars by February and the federal government is on the edge of bankruptcy.

Paul Ryan, the chairman of the House Budget Committee, said recently that while it was true nobody wanted the country to default, Republicans strived for cuts in spending along with a raise of the debt ceiling.