Talks between President Barack Obama and House Speaker John Boehner on a deal to avoid the fiscal cliff have turned more “serious,” aides said on Monday — but each side wants the other to be more specific about tax revenues and entitlement cuts.

Aides to the president asked Boehner and other Republicans to be more precise about higher taxes on wealthy Americans, while Boehner's representatives said they’re awaiting more details from Obama on spending reductions.

"We continue to wait for the president to identify the spending cuts he's willing to make," said Brendan Buck, a Boehner spokesman. "Discussions with the White House are taking place."

The House Speaker’s proposed plan includes $800 billion over 10 years in new tax revenues by closing loopholes and ending deductions.

But what is perhaps most striking — unlike in recent weeks — is that is that neither side is saying much publicly about what’s being discussed, longtime Washington observers tell The Wall Street Journal.

One congressional Republican said that, as in union negotiations, the most progress is made when the parties are not speaking before microphones.

Boehner and Obama met privately on Sunday for the first time in more than three weeks — and four days after they had last talked by telephone.

They have just 21 days to reach an agreement. If not, as much as $600 billion in drastic tax hikes and spending cuts will take place via sequestration on Jan. 2.

Recent posturing has centered mainly on what changes should be made to tax policy, while leaders last week discussed how to address the country's borrowing limit.

"Discussions with the White House are taking place, but we have no detail to share about the substance of those conversations,” Michael Steel, another Boehner spokesman, said on Monday.

“The Republican offer made last week remains the Republican offer, and we continue to wait for the president to identify the spending cuts he's willing to make as part of the 'balanced' approach he promised the American people."

For his part, White House spokesman Jay Carney declined to characterize the Obama-Boehner meeting, or how it would affect current negotiations. He was, however, optimistic about the prospects for a deal.

"The president does believe that we can reach an agreement," Carney said on Monday. "Our interest is in seeing if we can reach an agreement and not trying to negotiate an agreement through the media."

Obama also met with House Minority Leader Nancy Pelosi of California on Friday — and spoke with Senate Majority Leader Harry Reid of Nevada that same day. The president and Reid also talked on Monday.

And Obama only but briefly mentioned his proposed fiscal plan in a speech to workers on Monday at the Daimler Detroit Diesel plant in Redford, Mich. His plan seeks to raise top tax rates for high-income earners.

If no deal is reached, all of the George W. Bush-era tax cuts would expire on Dec. 31 — and the average family of four would see their tax bills go up by about $2,200, Obama said.

"That's a hit you can't afford to take," he said.

The president has long said that the government needs more revenue to help reduce the nation’s more than $16 trillion in debt.

Boehner and other Republicans say they oppose any increase in tax rates, and have proposed more revenues through ending loopholes and certain tax deductions.

But in calling for more details on tax revenues, Obama and aides questioned whether closing loopholes and ending deductions would raise the $800 billion claimed in the Republican plan without touching such popular deductions as for charitable contributions and home mortgage payments.

Republicans, meanwhile, still hope to find out how much the White House might agree to in spending cuts — and some GOP senators have said they would back higher tax rates on the very wealthy substantive cuts occur to programs like Social Security, Medicare, and Medicaid.

Still, neither side appears sure a deal will be reached. Boehner and Obama met extensively in summer 2011 to try to reach a deal on a broad-based plan to cut the deficit as part of an agreement to raise the debt ceiling, but those efforts collapsed.

"We can solve this problem," Obama said on Monday, a day after his private session with Boehner at the White House.



Information from The Wall Street Journal and USA Today was used to supplement this report.

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