President Barack Obama said Wednesday that congressional Republicans are pushing a radical plan to trim Medicare and Medicaid, ramping up the rhetoric as he and Congress approach crucial decisions on spending and the nation's debt.

"I think it's fair to say that their vision is radical," Obama told a town hall gathering at the headquarters of Facebook, the huge social network company.

"I don't think it's particularly courageous," he said of the GOP plan to convert Medicare to a voucher program and make big cuts to the federal-state Medicaid program for the poor.

"Nothing is easier than solving a problem on the backs of people who are poor, or people who are powerless, or don't have lobbyists, or don't have clout," Obama said.

Other Democrats have called the GOP plan radical, but the president generally has used less pungent language. Even as he sharply criticized the Republicans' spending proposals Wednesday, he said he believes the two parties can reach an accord on long-range plans to cut deficits by about $4 trillion over the next decade.

Obama made the comments in a friendly environment -- one with 19 million friends, in fact. He told Facebook employees and others watching online the nation must invest vigorously in education, clean energy and research that are vital to future jobs and a strong economy.

Making the case for his own deficit-cutting plans, Obama said that one way to trim health care costs could involve doctors sharing medical information on Facebook, the hugely successful social network.

Obama's 2008 campaign used Facebook and other social networks to reach voters, volunteers and donors, especially among young adults. Such outlets will play even bigger roles in next year's campaigns.

The president shared the stage with Facebook's youthful founder, Mark Zuckerberg, whose company noted that 19 million network users have electronically "liked" Obama's White House Facebook site.

Obama, beginning a three-day Western tour pitching his budget plans and raising re-election cash, said trimming $4 trillion from the nation's deficits over the next 12 years sounds like a lot but can be done.

He will hold another session Thursday in Reno, Nev., with his message that his approach to cutting deficits is more balanced and less painful than a rival House Republican plan.

The president has proposed cutting spending, raising taxes and squeezing federal health care programs. The Republican plan rules out tax cuts and would achieve nearly $6 trillion in savings from spending cuts and overhauling Medicare and Medicaid.