WASHINGTON — White House Press Secretary Jay Carney refused to rule out a radical proposal to mint a $1 trillion platinum coin that would allow the federal government to go around the debt ceiling if Congress refuses to act.

Briefing reporters Wednesday afternoon, Carney said, "There is no plan B, there is no backup plan" to Congress raising the nation's borrowing limit, but repeatedly declined to rule out the proposal to skirt the limit. "There is Congress's responsibility to pay the bills of the United States," he added.

Carney explicitly ruled out any White House staff efforts to negotiate with Congress over raising the debt limit, saying no one of the administration with engage in talks on raising the federal borrowing limit.

Under the proposal, the Treasury Department would mint a $1 trillion platinum coin by using a loophole in U.S. law allowing the department to mint platinum coins in any denomination, and then deposit the coin with the Federal Reserve to allow the Treasury to continue to pay its bills — by retiring debt — even if it can no longer borrow money.

"The option here is for Congress to do its job and pay its bills, bills that have already been racked up," Carney said later, again refusing to rule out the option. The White House has already ruled a proposal to lift the debt ceiling by executive order citing the 14th Amendment saying it believes it doesn't have the authority to do so.

Asked if he was aware of any administration officials examining the $1 trillion coin proposal. He replied with the non-Shermanesque, "Not that I know of."