In his weekly radio and Internet address, Obama said Medicare will exist for many more years, thanks to new legislation that helped put the health care program for America's seniors on stronger financial footing.
Seniors already are benefiting from that new health care law, said Obama, noting that many have received $250 rebates to help buy medicine, for example.
Obama said the law and efforts by his administration to eliminate waste, fraud and abuse both in Medicare and across government generally are making the program stronger and cutting health care costs for seniors.
"Medicare isn't just a program," Obama said."It's a commitment to America's seniors -- that after working your whole life, you've earned the security of quality health care you can afford."
"As long as I am president, that's a commitment this country is going to keep" he said.
An annual report this week from the trustees who oversee Medicare, including the Treasury and Health and Human Services secretaries, said the program will stay afloat for a dozen years longer than previously projected, due to the sweeping health care overhaul Obama signed in March.
But the added solvency also depends on cuts that ultimately may not be carried out.
In their weekly address, Republicans focused on the economy and taxes.
Illinois Rep. Peter Roskam criticized the government's spending and the prospect of higher taxes at a time of continued high unemployment. Obama wants to let a series of tax cuts for the wealthiest Americans that were enacted during the administration of Republican President George W. Bush expire on schedule in January. Republicans argue that such a move would further damage the economy.
"At a time of serious economic challenges, massive new tax increases are a surefire way to stall growth and prevent businesses from creating jobs," Roskam said. "That's because every dollar in new taxes owed is a dollar that can't be used to pay current employees or hire new workers."
"Hobbling the small businesses that are the backbone of our economy will further delay a robust recovery," he said.