WASHINGTON — President Barack Obama on Tuesday defended his $3.7 trillion budget plan for 2012 against criticism that it would drive up the nation's debt and that it fails to curb entitlement spending.

In a hastily called news conference at the White House, Obama also implored congressional lawmakers to resist making threats to shut down the government if they can't prevail on budget disputes, saying that would have a "destabilizing" impact on the economy and hurt individuals such as veterans and Social Security recipients.

He said he was prepared to negotiate with Republicans and Democrats "in a serious way" to contain Medicare and Medicaid costs, and that while Social Security needed "some modest adjustments" it wasn't as urgent a problem as the finances of the other two programs were.

Asked whether the uprising in Egypt could harm U.S. interests if similar movements take root broadly across the Middle East, Obama said his administration had been warning "friend and foe alike" in the region that "the world is changing, that you have a young, vibrant generation within the Middle East that is looking for greater opportunity and that if you are governing these countries, you've got to get out ahead of change. You can't be behind the curve."

"You can't maintain power through coercion. At some level, in any society, there has to be consent," Obama said.

"And that's particularly true in this new era, where people can communicate . . . on a smart phone or a Twitter account and mobilize hundreds of thousands of people."

Obama spoke as his budget director, Jacob Lew, faced withering criticism from Republicans and only a lukewarm reception from many Democrats when he testified before the House of Representatives Budget Committee.

"When it comes to the real issues facing our country, the president punted," House Speaker John Boehner, R-Ohio, said at a news conference.

Republicans haven't offered any specific entitlement spending-control plan, either.

(David Lightman contributed to this report.) MORE FROM MCCLATCHY

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