Sounding an optimistic note despite indications that talks to avert a series of tax increase and spending cuts remain at an impasse, President Obama predicted Tuesday that Republicans will eventually support extending current taxes rates for most Americans before the end of the year.

“I’m pretty confident that Republicans would not hold middle-class taxes hostage to trying to protect tax cuts for high-income individuals,” Obama said in an interview with ABC.

Obama added that he remains “optimistic” that a comprehensive deal can be reached.

“I’d like to see a big package. But the most important thing we can do is make sure that middle class taxes do not go up on Jan. 1,” Obama said.

Obama’s comments came during an interview Tuesday with Barbara Walters, portions of which aired Tuesday on “ABC World News with Diane Sawyer.”

The president’s comments echo similar statements made Tuesday by congressional Democrats, who said they are willing to negotiate significant spending cuts – including cuts to entitlement programs – but only if Republicans first agree to keep current tax rates for lower- and middle-income Americans while raising rates on top earners.

“If the Republicans can move on that [taxes] then we are prepared to do some tough things on the spending side,” Obama said in the ABC interview. “Taxes are going to go up one way or another. And I think the key is that taxes go up on high-end individuals.”

Among the potential areas for compromise, Obama left open the door to raising the Medicare eligibility age from 65 to 67.

“When you look at the evidence it’s not clear that it actually saves a lot of money,” he said. “But what I’ve said is let’s look at every avenue, because what is true is we need to strengthen Social Security, we need to strengthen Medicare for future generations, the current path is not sustainable because we’ve got an aging population and health care costs are shooting up so quickly.”

The rest of Walters’s interview with Obama is scheduled to air Friday night on an episode of “20/20” that is also scheduled to feature comments by First Lady Michelle Obama.