US Treasury Secretary Janet Yellen has urged Congress to raise the federal debt limit, warning a default by the United States would cause "an economic and financial catastrophe."

Yellen made the remarks at a news conference on Thursday in Niigata, central Japan, where she meets her counterparts and central bank governors from the Group of Seven industrialized countries.

The US Congress sets the federal government's debt limit for fiscal discipline, but it has already hit the ceiling.
It is pointed out that the US could default on its national debt as early as June 1, unless Congress lawmakers address the issue.

Yellen told reporters that a default would "produce an economic and financial catastrophe," and "millions of Americans could lose their jobs, household incomes would be reduced."

She added that it would spark a global downturn, risk undermining the US global economic leadership and raise questions about the country's ability to defend its national security interests.

The US Republican Party, which supports fiscal discipline, insists on spending cuts in federal expenditures, such as for climate measures, before raising the debt ceiling. The administration of Democrat President Joe Biden is opposed to a reduction in spending.

Tuesday's meeting between Biden and House GOP Speaker Kevin McCarthy failed to narrow their differences over the debt ceiling dilemma. They are expected to meet again on Friday.