Pelosi's position, revealed in an exclusive interview with ABC News' Diane Sawyer, came a day after a group of senators announced a bipartisan resolution condemning the Bush administration's plan to increase U.S. forces in Iraq by more than 20,000 troops.
While the Senate resolution would be non-binding, it would send a message to the president, and at least a dozen Republican senators have already offered their support.
Below is an excerpt from Sawyer's interview, in which Pelosi said Democrats in Congress would not be held responsible for putting the soldiers in the troop surge in additional harm's way by blocking funds.
The complete interview with Pelosi will air tomorrow morning on "Good Morning America."
Sawyer: As we sit here right now, 3,500 troops are moving in. That's the first of the surge. It has begun. Fifty-one percent of the American people say they want Congress to stop the surge. Money is the method at hand to do that.
Are you going to move to cut off funding for troops going into Iraq as part of the surge?
Pelosi: Democrats will never cut off funding for our troops when they are in harm's way.
It is, I think, very difficult for the president to sustain a war of this magnitude without the support of the American people and without the support of the Congress of the United States. That's why Congress will vote to oppose the president's escalation, from the standpoint of policy. We will have our disagreement.
Sawyer: But short of that — questions posed, resolutions passed — short of that, are you acquiescing in the surge if the pocketbook is the only other control mechanism?
Pelosi: The president knows that because the troops are in harm's way, that we won't cut off the resources. That's why he's moving so quickly to put them in harm's way.
But we will hold the president accountable. He has to answer for his war.