Updated, 3:37 p.m.

Senate Majority Leader Harry Reid (D-Nev.) told reporters on a conference call today that he is developing a “backup plan” to extend the payroll tax cut if a bicameral conference committee fails.

Reid said Democrats “will not rest” until the payroll tax cut and unemployment benefits are extended. He said top Democrats are working on a backup plan, although he declined to discuss details.

“If we have to put it forward, we will,” he said.

Reid also warned Republicans against slow-walking the president’s agenda.

“We’re more than a month into the new year,” he said. “They are still arguing over whether they should have a positive agenda.”

Reid urged Republicans to quickly agree to a payroll tax cut and work on other agenda items, instead of focusing on the elections and defeating the president.

“I hope my Republican colleagues will come to their senses soon,” he said.

Speaker John Boehner (R-Ohio) responded to Reid’s disclosure of a backup plan by urging Democrats to focus on reaching a deal in the conference. Boehner said Democrats should embrace items such as instituting a freeze on federal pay, which was overwhelmingly passed in the House this week. Boehner said Democrats have yet to offer a full plan in the talks.

“You can’t have a ‘backup plan’ if you haven’t offered anything to back up,” Boehner said. “The House has put a plan on the table as the basis for negotiations: the bill passed by the House, which extends the payroll tax cut and unemployment insurance for a full year, offset almost entirely with spending cuts the president himself has endorsed.”

Reid also dismissed Republican attacks over the failure of Democrats to bring a budget resolution to the Senate floor since 2009, and he said Senate Democrats would not vote on their own budget this year.

Reid said the Budget Control Act passed last year as part of the deal to raise the debt limit is stronger than a nonbinding budget resolution, and appropriations committees are already at work building off the spending levels set by that law.

“They haven’t anything better to do,” Reid said of GOP attacks. “We have a law, not some idea, not some wish,” he said.

“We do not need to bring a budget to the floor this year. … We already did it,” he added.

Reid added that Senate Budget Chairman Kent Conrad (D-N.D.) “may mark something up in his Budget Committee … but it doesn’t have to come to the floor.”

Sen. Charles Schumer (D-N.Y.) objected to a Roll Call reporter’s question about the budget.

“That question is like asking whether you will pass a bill on insider trading,” Schumer said. “We did.”

Schumer, meanwhile, said there was “great potential” to compromise on a small-business tax cut with House Republicans, but he warned the GOP against blocking efforts to boost the economy.

“Republicans will be judged on whether they are constructive or not,” he said.