President Barack Obama warned of a \"deep economic crisis\" if the United States fails to raise its debt limit and urged Americans to pressure Republican lawmakers to compromise to avert a default. In a televised addresss late Monday only eight days before Washington begins to run out of money to pay its bills, Obama called the weeks-long debt talks stalemate \"a dangerous game\" that the country \"cannot afford to play.\" As the president spoke from the East Room of the White House, the dollar plunged to a four month low in Tokyo amid growing jitters as the impasse between Republicans and Democrats over the US debt crisis deepened. Obama cast the blame for the stalemate on the Republicans\' refusal to raise the $14.3 trillion debt ceiling unless there is agreement to make deep spending cuts without increasing taxes on the wealthy. If Congress fails to raise the ceiling by August 2, the resulting economic disaster could include higher interest rates for the US government as well as for consumers. Failure to compromise, Obama said in his speech from the White House, \"would risk sparking a deep economic crisis -- one caused almost entirely by Washington.\" He rejected a Republican proposal for a temporary increase in the debt limit, arguing it would leave the underlying problem unresolved and lead to a repeat of the current crisis in just six months\' time. \"That is no way to run the greatest country on Earth. It is a dangerous game we\'ve never played before, and we can\'t afford to play it now,\" he said. With a potential US default as of a week from Tuesday, Obama appealed to Americans to \"make your voice heard\" to members of Congress. Many Americans appeared to have heeded the president\'s call. US media reported that various congressional websites -- including those for prominent Republicans like House Speaker John Boehner, House Majority Whip Kevin McCarthy, and congresswoman and presidential contender Michele Bachmann -- were inaccessible, after an apparent server crash following the speech. Obama\'s primetime speech late Monday was only his seventh formal address to the nation, and the first since he unveiled a timeline for a US troop withdrawal from Afghanistan in June. Boehner, the Republican leader of the US House of Representatives, responded with a late-night speech of his own, blaming Obama for the crisis and warning that while the US cannot default on its debt obligations, Americans nevertheless would demand deep spending cuts. Boehner -- who has flatly rejected Obama\'s call to increase taxes on the rich and wealthy corporations -- is proposing a two-step plan with debt increases first to February or March 2012, and later to 2013. \"Time is running short and it would be irresponsible for the president to veto this common-sense plan and run the risk of default,\" said Boehner. \"I would encourage the Senate to pass this plan and the president to sign it,\" he said, portraying Obama as the inflexible party in the protracted debt negotiations. \"The sad truth is that the president wanted a blank check six months ago, and he wants a blank check today.\" The prospect of the world\'s richest country running out of cash to pay its bills come next Tuesday sent stocks sliding and gold soaring, while the IMF warned of a \"severe shock\" to the world economy absent an elusive breakthrough. All sides in the dispute agree Washington must reduce its deficit but disagree on the size and blend of spending cuts and revenue increases as well as on how and whether to slice into the social safety net. Washington hit its debt ceiling on May 16 but has used spending and accounting adjustments, as well as higher-than-expected tax receipts, to continue operating normally but can only do so through August 2. At that point, US leaders will face an agonizing choice about cutting an estimated 40 cents of every dollar in spending and defaulting either on debt payments or on other obligations like government health or retirement benefits. Meanwhile, there were signs the stand-off was exacting a political toll on both the president and Republicans. A poll for the Washington Post and ABC television showed weakening support for Obama\'s economic agenda, and found the percentage of people who said he has made the economy worse has jumped six points since October to 37 percent. Republicans also took a hit in Americans\' esteem. About as many people blamed Republican policies for the economy\'s woes as they do Obama. But the poll also found that 65 percent disapproved of the GOP\'s handling of jobs -- still the top economic issue -- compared to 52 percent for the president. The International Monetary Fund pressed US politicians to raise the debt ceiling \"expeditiously to avoid a severe shock to the US economy and world financial markets\" with the deadline now looming large.