Obama told a news conference, meanwhile, that the budget he sent Congress will help meet his goal of cutting the deficit in half by the end of his first term and said he hoped to find common ground with Republicans. He also defended his decision to avoid overhauls in entitlement programs like Social Security and Medicare, saying the two parties need to work together to find compromise.

"There's going to be a lot of ups and downs in the coming months as we get to that solution," the president said. "I'm confident that we can get this done."

House Republicans, though, were eager to launch a weeklong debate on their own package of deep cuts in domestic spending for the current fiscal year.

White House budget director Jacob Lew kicked off the administration's defense of its proposed 2012 budget on Capitol Hill with an appearance before the House Budget Committee. Rep. Mike Simpson spoke for most of the Republicans on the panel in saying he doesn't view the proposal — which mostly ignores the recommendations of Obama's fiscal commission — as a serious one.