WASHINGTON – For the first time in days, President Obama and House Speaker John Boehner spoke by phone Wednesday about the “fiscal cliff” that threatens to knock the economy into recession, raising the prospect of fresh negotiations to prevent tax increases and spending cuts set to kick in Jan. 1.

Officials provided no details of the conversation, which came on the same day the president, hewing to a hard line, publicly warned congressional Republicans not to inject the threat of a government default into the already complex issue.

“It’s not a game I will play,” Obama told a group of business leaders as Republicans struggled to find their footing in talks with a recently re-elected president and unified congressional Democrats.

Among the Republicans, Sen. Tom Coburn of Oklahoma became the latest to break ranks and say he could support Obama’s demand for an increase in tax rates on upper incomes as part of a comprehensive plan to cut federal deficits.

Across the Capitol, House Majority Leader Eric Cantor said Republicans want to “sit down with the president. We want to talk specifics.” He noted that Republicans had made a compromise offer earlier in the week and the White House had rejected it.

Officials said after the talk between Obama and Boehner, R-Ohio, there was no immediate plan for a resumption of negotiations to avert the cliff. At the same time, they said that for the first time in a few days, at least one top presidential aide had been in touch with Republicans by email on the subject.

Each side has been declaring that the crisis can be averted if the other will give ground.

“We can probably solve this in about a week, it’s not that tough,” Obama said in lunchtime remarks to the Business Roundtable.

It has been several days since either the president or congressional Democrats signaled any interest in negotiations that both sides say are essential to a compromise. Presidential aides have even encouraged speculation that Obama is willing to let the economy go over the “fiscal cliff” if necessary and gamble that the public blames Republicans for any fallout.

Eventually, Democrats acknowledge, there will be compromise talks, possibly quite soon, toward an agreement that raises revenues, reins in Medicare and other government benefit programs, and perhaps raises the government’s $16.4 trillion borrowing limit.

For now, the demonstration of presidential inflexibility appears designed to show that, unlike two years ago, Obama will refuse to sign legislation extending top-rate tax cuts and also to allow public and private pressure to build on the Republican leadership.