UPDATE 1-White House: Obama would sign short-term debt limit increase

WASHINGTON, Jan 22 (Reuters) - The White House on Monday welcomed signals by Republican leaders in the House of Representatives that they aim to pass a nearly four-month extension of the U.S. debt limit, saying the move defuses fears of a damaging U.S. debt default.

White House spokesman Jay Carney said in a briefing that the Obama administration believed the debt limit should be raised over the longer term instead of in incremental steps, but the shift by House Republicans was a positive sign.

"What happened ... was a very significant development in terms of de-escalating the sense of conflict over this," Carney said.

President Barack Obama would not block a short-term extension if it passed Congress, he added.

"The bill still has to overcome some concerns expressed by members of the House and the Senate before it can pass both chambers and reach the president's desk," Carney said. "If it does, and it reaches the president's desk, he would not stand in the way of the bill becoming law."

The United States is due to run out of room under its congressionally-imposed borrowing limit of $16.4 trillion sometime between mid-February and early March. Congressional Republicans have in the past balked at raising the cap, insisting on matching or greater spending cuts in exchange, and raising the specter of default as a bargaining chip.

But they backed down from that hard line stance at a policy retreat last week, shifting the focus of budget battles with the White House to a March 1 date for automatic deep spending cuts and a March 27 expiration of funding for government agencies and programs. The debt ceiling extension would satisfy borrowing needs to at least May 19.