WASHINGTON (CNN) -- House Speaker Nancy Pelosi said Monday Democrats will not cut off funding for the war in Iraq, despite indicating earlier that she will not give President Bush a "blank check" to fund a U.S. troop surge in the war-torn country.

"I'm going to be very clear: Democrats will not cut off funding for our troops," Pelosi told reporters on Capitol Hill. "But the president needs to know -- and that's what I was telling him yesterday -- ... that congressional oversight is alive and well."

On CBS' "Face the Nation" on Sunday, Pelosi said, "If the president wants to add to this mission, he is going to have to justify it. And this is new for him because up until now the Republican Congress has given him a blank check with no oversight, no standards, no conditions."

The president is expected to call for a troop surge during a prime-time address Wednesday night.