Obama: Republicans blocking middle-class tax cuts

The Democratic-controlled Senate has approved the measure, but Obama said House Republicans have "put forward an unbalanced plan that actually lowers rates for the wealthiest Americans." Obama supports a plan to raise taxes on families earning more than $250,000.

In his weekly radio and Internet address, Obama said "the math just doesn't work" on the GOP plan.

Obama's comments mark the fourth time since his re-election that he has used the radio address to push for middle-class tax cuts as part of a plan to avert a looming fiscal cliff — and his most sharply partisan tone.

Obama said his plan to raise taxes on the wealthiest Americans should come as no surprise to Republicans or anyone else.

"After all, this was a central question in the election. A clear majority of Americans — Democrats, Republicans and independents — agreed with a balanced approach that asks something from everyone, but a little more from those who can most afford it," Obama said.

His plan is "the only way to put our economy on a sustainable path without asking even more from the middle class," Obama said. It also is the only plan he is willing to sign, the president said.