WASHINGTON (AP) -- Senate Majority Leader Mitch McConnell of Kentucky and other congressional leaders are expressing doubts about Congress signing off on a historic agreement with Iran to address that country's nuclear program.

McConnell says on "Fox News Sunday" that the deal will be "a very hard sell" for the Obama administration in Congress.

McConnell spoke shortly after diplomats said on Sunday that negotiators at the Iran nuclear talks were expected to reach a provisional agreement to curb the country's atomic program in return for sanctions relief.

New Jersey Sen. Bob Menendez, the top Democrat on the Senate Foreign Relations Committee, says the pending deal makes him anxious because the U.S. has gone from making sure Iran does not have nuclear capability to managing it.

Menendez spoke on ABC's "This Week."

By AP