The U.S. Treasury Department announced Monday that the federal government expected to borrow 592 billion U.S. dollars from the market to fund its operation in the second half of this year, fresh evidence of the budgetary pressure facing the world's largest economy.

"During the July-September 2012 quarter, Treasury expects to issue 276 billion U.S. dollars in net marketable debt, assuming an end-of-September cash balance of 60 billion dollars," the department said in a statement.

The department forecast to issue 316 billion dollars in net marketable debt during the October-December quarter, assuming an end-of-December cash balance of 40 billion dollars.

U.S. economic activity has moderated in recent months, with growth held back by a number of temporary factors including the run-up in energy prices earlier this year, unusually warm winter weather, and the ongoing sovereign debt crisis in Europe, said Janice Eberly, Assistant Treasury Secretary for Economic Policy, in a separate statement released Monday.

Cuts in U.S. government spending continued to weigh on the economic activity in the second quarter, with state and local government outlays falling for the 11th straight quarter, Eberly added.