WASHINGTON —  President Barack Obama says House Speaker John Boehner and Senate Majority Leader Harry Reid are meeting on Capitol Hill this afternoon to try to hammer out a budget deal and avoid a government shutdown.

Saying it would be "inexcusable" for lawmakers to fail, Obama vowed to summon Boehner and Reid back to the White House tomorrow if they don't reach an agreement to fund the government through the end of the year.

Making an unscheduled appearance in the White House briefing room, he told reporters that he and his team are "prepared to meet for as long as possible to get this resolved."

Boehner says he too wants to avoid a government shutdown, but Republicans also want the largest spending cuts possible.

He says the GOP believes cutting spending will help create jobs.

Boehner has proposed an agreement that would keep the government running for one more week and slash another $12 billion in spending.

Obama says he could accept an extension of two or three days, but he's ruling out anything longer. He says he can't have federal agencies "making plans based on two week budgets."