WASHINGTON — President Barack Obama urged Congress on Monday to lift the nations debt ceiling without spending cuts, warning of dire consequences to the economy if lawmakers again push deliberations to the brink.In the last news conference of his first term, Obama said he wouldnt negotiate with congressional Republicans who wanted to use the obligation to lift the debt ceiling as an opportunity to curtail federal spending. They will not collect a ransom in exchange for not crashing the American economy, the president said. The full faith and credit of the United States of America is not a bargaining chip.The tough talk came as Obama prepares to take his second oath of office and a new fiscal crisis looms, just two weeks after he and Congress tussled over a New Years deal to avoid a series of tax hikes and deep spending cuts.That deal didnt include raising the $16.4 trillion debt ceiling, which the Treasury Department said was reached Dec. 31. Treasury has tapped emergency borrowing authority to pay creditors, but that fix is fast expiring and the president warned Monday that time is running short.He urged Congress to raise the debt ceiling without conditions and focus on a new fiscal plan to reduce the budget deficit by cutting spending and raising new revenue. He argued that the results of the November election show that voters side with his economic prescription.It turns out the American people agreed with me," he said. "They want us to get our books in order in a balanced way, where everybody pulls their weight, everyone does their part.He said hed be open to modest adjustments to programs such as Medicare, but he argued that the deficit cant be solved by spending cuts alone. And he argued that lawmakers would risk the nations reputation by haggling over the debt ceiling  risking a credit downgrade like the one imposed in 2011 after a fight over raising the debt ceiling.To even entertain the idea of this happening, of the United States of America not paying its bills, is irresponsible, he said. Obama argued that raising the debt ceiling pays for expenses that already have accrued, likening the debate to arguing over a restaurant check once the diner has polished off his plate. And he warned that failing to lift the ceiling might delay Social Security checks and veterans benefits.He brushed aside suggestions from congressional Democrats that he invoke an obscure provision in the Constitution to pay increased debt without congressional approval. There are no magic tricks here. There are no loopholes, the president said. What I will not do is to have that negotiation with a gun at the head of the American people, he said. The threat that unless we get our way, unless you gut Medicare or Medicaid . . . that were going to threaten to wreck the entire economy. That is not how historically this has been done. Thats not how were going to do it this time.Republicans reacted with some history of their own, noting that Obama had voted against raising the debt ceiling when he was a senator and George W. Bush was president. The president says he will not negotiate on cutting spending as part of raising the debt ceiling, but he voted against raising the debt ceiling as a United States senator, saying that to increase the debt ceiling constituted a sign of leadership failure,  said Rep. Cathy McMorris Rodgers, R-Wash, the chairwoman of the House Republican Conference. The president and his allies need to get serious about spending, and the debt-limit debate is the perfect time for it, Senate Republican leader Mitch McConnell of Kentucky said in a statement.A month to the day of the elementary school shooting in Newtown, Conn., Obama said he expected later this week to present his proposals for reducing gun violence. He said he intended to vigorously pursue them, but he acknowledged that Congress is unlikely to do all that he asks.Will all of them get through this Congress? I dont know, the president said, adding, If there is a step we can take that will save even one child from what happened in Newtown, we should take that step.Obama declined to offer specifics on what hell propose. But he said he continued to support more stringent background checks, a meaningful assault-weapons ban and the ability to keep high-capacity magazine clips out of the hands of folks who shouldnt have them.The administration also is expected to pursue some measures it can enact without congressional authorization, including improving how it tracks guns that fall into the hands of criminals.The president warned against a "rush to judgment," after criticism that thus far hes picked only white men for top Cabinet positions in his second term. He argued that he had as diverse if not a more diverse White House and Cabinet in his first term than other administrations, and that hed build on that record in his second."Until youve seen what my overall team looks like, its premature to assume that somehow were going backwards, he said. Were not going backwards, were going forward. David Lightman contributed to this report. 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