WASHINGTON – Fiscal cliff talks at a partisan standoff, President Obama and House Speaker John Boehner swapped barbed political charges on Wednesday yet carefully left room for further negotiations on an elusive deal to head off year-end tax increases and spending cuts that threaten the national economy.

Republicans should “peel off the war paint” and take the deal he’s offering, Obama said sharply at the White House. He buttressed his case by noting he had won re-election with a call for higher taxes on the wealthy, then added pointedly that the nation aches for conciliation, not a contest of ideologies, after last week’s mass murder at a Connecticut elementary school.

But he drew a quick retort from Boehner when the White House threatened to veto a fallback bill drafted by House Republicans that would prevent tax increases for all but million-dollar earners. The president will bear responsibility for “the largest tax increase in history” if he makes good on that threat, the Ohio Republican declared.

In fact, it’s unlikely the legislation will get that far as divided government careens into the final few days of a struggle that affects the pocketbooks of millions and blends lasting policy differences with deep political mistrust.

Boehner expressed confidence the Republicans’ narrow so-called Plan B bill would clear the House today despite opposition from some conservative, anti-tax dissidents, but a cold reception awaits in the Democratic-controlled Senate.

As for a broader agreement, officials said there had been little if any progress toward closing the gap between the two sides in the past two days, even though aides to the president and Boehner have remained in contact.

On paper, the two sides are relatively close to an agreement on major issues, each having offered concessions in an intensive round of talks that began late last week.

But political considerations are substantial, particularly for Republicans.

After two decades of resolutely opposing any tax increases, Boehner is seeking votes from fellow Republicans for legislation that tacitly lets rates rise on million-dollar income tax filers.

The measure would raise revenue by slightly more than $300 billion over a decade than if all of the Bush-era tax cuts remained in effect.

But Boehner’s office trumpeted another figure – an estimate that claimed it would amount to a tax cut of nearly $4 trillion compared with what would happen if all those tax cuts were to expire as scheduled with the turn of the year.

Similarly, despite vehement protests that the looming across-the-board spending cuts would seriously affect the Pentagon, the leadership’s fallback bill does nothing to blunt or eliminate the reductions scheduled to begin on Jan. 1

At the White House, Obama repeated that he is ready to agree to significant spending cuts that might cause distress among some fellow Democrats, but he saved his sharpest words for Republicans.

“Goodness, if this past week has done anything, it should just give us some perspective,” he said in a reference to the shootings of school children in Connecticut.

Yet even as he implored Republicans to “take the deal,” he made it clear he’s open to more bargaining.