With just 12 days until tax increases and steep spending cuts kick in, President Obama today urged Republicans to "peel off the partisan war paint" and compromise on a deal to avoid going over the "fiscal cliff."

Speaking at a White House news conference, Obama told House Republicans to "take the deal" and said it was puzzling that they had not accepted what he described as a "fair" offer.

"They will be able to claim that they have worked with me over the last two years to reduce the deficit more than any other deficit reduction package, that we will have stabilized it for 10 years," he said. "That is a significant achievement for them. They should be proud of it. But they keep on finding ways to say no, as opposed to finding ways to say yes.

"I don't know how much of that just has to do with, you know, it is very hard for them to say yes to me," he added. "At some point, you know, they've got to take me out of it and think about their voters and think about what's best for the country."

After the massacre at Sandy Hook Elementary School, the president said, the country needs to see its leaders working together to compromise.

"If there's one thing we should have after this week, it should be a sense of perspective about what's important," he said.

Obama's comments at a news conference announcing a new task force on gun violence came shortly after the White House slammed House Speaker John Boehner's "Plan B" proposal to extend the current tax rates for those earning less than $1 million a year. He threatened to veto it.

"They're thinking about voting for raising taxes, at least on folks [with annual incomes] over a million, which they say they don't want to do - but they're going to reject spending cuts that they say they do want to do," the president said. "That defies logic. There's no explanation for that. You know, I think that any objective person out there looking would say that, you know, we put forward a very balanced plan, and it's time for us to go ahead and get it done."

Obama said the proposals that he and Boehner, R-Ohio, have put forth are "actually pretty close" and that he remains optimistic a deal can be reached.

"I'd like to get it done before Christmas," Obama said. "There's been a lot of posturing up on Capitol Hill instead of just going ahead and getting stuff done. And we've been wasting a lot of time. It is the right thing to do. I'm prepared to get it done. But they're going to have to go ahead and make some adjustments."

Obama's latest offer dropped his demand that tax rates go up on those making more than $250,000, raising the threshold to incomes above $400,000, and lowered his revenue target to $1.2 trillion over 10 years. It also offered more limits on entitlement spending, including slower annual cost-of-living increases for Social Security beneficiaries.

Boehner has called the offer unbalanced, but pledged to continue negotiating.