J. Scott Applewhite/AP Photo

House Republicans said today they would be willing to interrupt their upcoming five week recess and return to Washington if the Senate comes up with a package of budget reforms that would avoid massive cuts in defense funding.

The promise - and politically loaded challenge - came in a letter signed by the top four House Republicans - House Speaker John Boehner, Majority Leader Eric Cantor, Majority Whip Kevin McCarthy and Conference Chairman Jeb Hensarling.

The Budget Control Act, signed into law last summer, requires $1.2 trillion in automatic cuts equally divided between defense and domestic programs, over the next decade if Congress can't agree on a budget. They have five months left to reach agreement, but appear to be deadlocked.

The initial round of cuts, called the defense sequester, would total $109 billion starting on Jan. 2, 2013.

"If the Senate passes its own package of alternative cuts and reforms to replace the defense sequester, it is our commitment that the House will reconvene to either consider it or to go to conference to produce a consensus package that can be sent to the president for his signature," the GOP quartet writes in the letter. "However, in order to avert the threat to our nation's security that is posed by the defense sequester, the Senate must act. A Senate vote to simply postpone the sequester, rather than replace it with common-sense cuts and reforms, is unworkable and unacceptable."

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According to prepared excerpts from Boehner's remarks to the GOP Conference, the speaker intended to tell his rank and file members that the GOP is putting the onus on the Senate to act.

"We're putting this right at your doorstep. You own it," he'll say of the Democrats. "If Harry Reid, Nancy Pelosi and Barack Obama want to own a small business tax hike and a devastating cut to our national defense, they are now set up perfectly to do so."