The White House has rejected a series of leaked reports saying Obama has already made up his mind to send thousands more troops to Afghanistan. It says no decision has been made.
Sunday's raids appeared to be one of the largest hauls of the war so far and Nato officials expressed hope that the seizure would hurt Taliban fighters, whose homemade bombs have become the biggest killer of foreign forces.
Acting on a tip, international forces and Afghan police discovered 1,000 45kg bags of ammonium nitrate fertiliser and 5,000 parts for roadside bombs in a warehouse.
An additional 4,000 45kg bags of fertiliser were found in a nearby compound soon after.
The seizure included enough fertiliser to make hundreds of roadside bombs, John Pike, director of the military think-tank Globalsecurity, said.
Weapons on display
The find comes a day after Al Jazeera obtained exclusive footage of Taliban fighters brandishing what appeared to be US weapons.
The fighters say they seized the arms cache from two US outposts in eastern Nuristan province which the US military abandoned last month.
Taliban fighters brandish what they say are US weapons seized from abandoned outposts
Angela Eggman, a Nato spokeswoman, said it was not clear from the video where or when the weapons were obtained.
"Before departing the base, the units removed all sensitive items and accounted for them," she said.
But General Mohammad Qassim Jangulbagh, Nuristan's provincial police chief, disagreed, saying: "The Americans left ammunition at the base."
Farooq Khan, a spokesman for the Afghan National Police in Nuristan province, concurred, saying US forces left arms and ammunition when they moved from the area, which he said was now in fighters' hands.
The Pentagon said the closing of the outposts in Nuristan was part of plans by General Stanley McChrystal, the US and Nato commander in Afghanistan, to shut down isolated units and focus on more heavily populated areas.