Fresh off last week's down-to-the-wire spending showdown, President Obama and Speaker John Boehner are locking horns again on fiscal matters — and this time the stakes for the U.S. economy are even more monumental.

The White House is demanding a "clean" bill to raise the nation's debt ceiling rather than using it to cut additional spending or for policy additions like last week's attempt to attach legislation defunding Planned Parenthood, but Boehner has already said that idea is dead on arrival. There's no way a debt-ceiling bill would pass the House (i.e. the muster of his unruly GOP conference) without some spending cuts for balance.

Unlike in the beginning of the battle over this year's spending plan, the rhetoric over the debt ceiling is already white hot. White House spokesman Jay Carney on Monday said the consequences of failing to raise the debt ceiling would be "Armageddon-like" for the country.

"We cannot play chicken with the economy in this way," Carney told reporters at a briefing. "It's just too darn risky. It's not appropriate."

At the same time, Obama is taking the expected round of hits for his vote while a senator in 2006, refusing to raise the debt ceiling. Carney on Monday acknowledged that vote was a mistake and the President realizes now that the debt ceiling is too important to tamper with.

The Republican National Committee issued an especially stinging zinger: "[Sen.] John Kerry [D-MA] called and he wants his flip-flops back," blasted the release.

Treasury Secretary Tim Geithner sent a letter to Congress last week predicting the government will reach its debt limit by May 16 and would only have until early July before it would default on its loans if the ceiling is not raised.

Defaulting on the loans is not an option and would have a disastrous impact on the economy.

"The U.S. needs to be credit worthy," Carney said. "Anything Congress would do to suggest that the U.S. is not credit worthy would be calamitous."

Obama plans to give what the White House is billing as a landmark speech on his plans for reducing the country's deficit on Wednesday at George Washington University.

Carney would not reveal any details of the speech, arguing that he did not want to "preview" it's contents, saying only that his plans for reducing spending would provide "shared sacrifices" and would not cut services to the poor while decreasing tax cuts for the wealthy.

Republished with permission from TalkingPointsMemo.com. Authored by Susan Crabtree. Photo via AP. TPM provides breaking news, investigative reporting and smart analysis of politics.