Sen. Bob Corker (R-Tenn.) said Sunday that he believes Republicans would consider adding new tax revenues by closing loopholes if Democrats show a willingness to embrace "true" entitlement reform.

"I think Republicans, if they saw true entitlement reform, would be glad to look at tax reform that generates additional revenues," Corker said on "Fox News Sunday." "And that doesn't mean increasing rates, that means closing loopholes. It also means arranging our tax system so that we have economic growth."

In the debate over the nation's budget, Democrats have called for a plan that includes new tax revenue, while most Republicans have argued against adding any new taxes.

In an interview with ABC News's "This Week With George Stephanopoulos," House Speaker John Boehner (R-Ohio) kept up a hard line against the prospect of adding new tax revenue.

“The talk about raising revenue is over. It’s time to deal with the spending problem,” Boehner said.

Sen. Dick Durbin (D-Ill.), the Senate's second-ranking Democrat, said he was open to reforms to Medicare, but didn't delve into specifics, as he criticized the House Republican plan.

"We want to make sure Medicare is there for generations to come," Durbin said on "Fox News Sunday." "And that means making some reforms and some constructive changes. The Paul Ryan voucher approach is destructive."