House Speaker John Boehner on Sunday said he was "flabbergasted" by the White House's opening proposal to avert economically devastating tax increases and spending cuts set to take effect Jan. 1, calling negotiations on the so-called fiscal cliff deadlocked with just weeks remaining to find a compromise.

"You can't be serious," the Ohio Republican said he told Treasury Secretary Timothy Geithner, President Obama's point man on the negotiations.

"The president and the White House have three weeks, and this is the best we got?" Boehner said on "Fox News Sunday." "The president's idea of a negotiation is 'Roll over and do what I ask.' "

The White House last week called for $1.6 trillion in higher taxes over the next decade and $600 billion in spending cuts, primarily from Medicare.

The plan would also give the president authority to raise the federal government's borrowing limit without congressional approval, a proposal Boehner said is a nonstarter for lawmakers.

"Congress is never going to give up this power," he said. "It's the only way to leverage the political process to produce more change than what it would have left alone."

If Congress and the White House fail to reach a deal by the end of the month, taxes will go up on the average family by $3,500 next year and $1.2 trillion in federal spending cuts, largely from the Pentagon's budget, would begin.

Geithner, making the rounds on the Sunday talk shows, insisted that if Republicans don't sign off on Obama's plan to raise taxes on the wealthy, they'd be responsible for the economic devastation caused by the resulting plunge over the fiscal cliff.

"The ball really is with them now," Geithner said. "There's not going to be an agreement without rates going up."

Geithner said the administration preferred to reset the top income tax rate at 39.6 percent for families making more than $250,000 annually -- the rate during Bill Clinton's presidency -- but refused to rule out a compromise that would stop short of that figure.

Republicans oppose outright any increase in the tax rate but say they are open to raising new revenue by closing tax loopholes.

The GOP called on Democrats to agree to reforms to entitlement programs like Medicare to demonstrate that they're serous about deficit reduction. But Geithner on Sunday only dug in further on entitlement reform, saying changes to the Social Security system would not be part of any deficit reduction deal.

Talks over the fiscal cliff have made so little progress that some lawmakers question whether a deal is possible.

"I think we're going over the cliff," Sen. Lindsey Graham, R-S.C., said on CBS' "Face the Nation."

Added Sen. Mark Warner, D-Va. on CNN's "State of the Union," "We've got to get past the kind of Washington decoder speak and say specifically, 'How do we get there?' We need to go ahead and lay down what we're going to get done before the end of the year, and then how we get to that."

The president, who took his case for tax increases to the American people last week, will continue that effort this week during White House meetings with governors and business leaders.