JABAL OS SARAJ, Afghanistan — After years of stalemated civil war in Afghanistan, the opposition to the ruling Taliban is increasingly confident of ridding the country of its radical Islamic leadership.

The Taliban have held power since 1996, when they ousted President Burhanuddin Rabbani's government.

Rabbani's foreign minister predicted sweeping defections from the Taliban amid the growing unrest: Yesterday, the former U.S. Embassy in Kabul was attacked, clashes with opposition forces were reported in the north and the U.S. continued deploying forces for possible military strikes.

Already, many Taliban fighters want to defect to the opposition, said the foreign minister, Abdullah, who like many Afghans uses only one name.

Thousands of protesters burned an effigy of President Bush then stormed the abandoned U.S. Embassy in the Afghan capital yesterday, torching old cars and a guardhouse and tearing down the U.S. seal above the entrance. The old embassy compound was guarded by a few Afghan security guards who were no match for the crowd. The last U.S. diplomats left the embassy in January 1989 just ahead of the Soviet withdrawal from Afghanistan.

In northern Afghanistan, where the Northern Alliance is fighting Taliban troops, heavy new fighting was reported. Radio Kabul quoted government officials as saying Taliban forces pushed back opposition troops in the Razi district of Badghis province in northwestern Afghanistan.

Mohammed Ashraf Nadeem, a spokesman for the opposition's Northern Alliance, said both sides used artillery, rocket launchers, tanks and machine guns, but neither could take over new territory.

Nadeem, reached by telephone from Kabul, the capital, said the Taliban had rushed 3,000 new troops to the region from Kandahar, the southern city where the Taliban are based.

The Northern Alliance represents a coalition of ethnic and political factions that banded together to resist the Taliban, who have imposed their rigid interpretation of Islam on most of the country. A major component of the alliance is the former Afghan government that the Taliban drove from Kabul in 1996.

The rebels control 10 percent or less of Afghanistan but say they have 15,000 armed fighters and an intimate knowledge of the territory that could be invaluable for the U.S. military.

The Northern Alliance forces suffered a serious setback with the assassination of military leader Ahmed Shah Massood by suicide bombers this month. But U.S. threats of military action against the Taliban for harboring Osama bin Laden, the man accused of masterminding the Sept. 11 terrorist attacks on the United States, have dramatically shifted the odds in Afghanistan's 12-year civil war.

The alliance's Abdullah said that consultations between Rabbani's representatives and U.S. officials were intensifying but that he had no knowledge of when any American military action against Taliban-held areas of Afghanistan might begin.

Abdullah, speaking in English at a news conference for foreign journalists in this town north of Kabul, hinted that his government was briefing the U.S. on potential military targets.

According to Abdullah, Kabul would not be the first target for Northern Alliance forces. He spelled out a possible international strategy if the Taliban fall: Demilitarize Kabul and bring in U.N. peacekeepers.

"In my opinion, it is very important to increase the role of the U.N. at this stage. I think if the Taliban forces are defeated somehow in the coming days or weeks, the issue of Kabul will become even more important because of the vacuum that will be left behind," he said.

According to Abdullah, there has been increasing communication between the Northern Alliance and disloyal members of the Taliban who are eager to swap sides.

"If we open the gate, there will be defections on a daily basis. But we are working on a larger plan in that regard, and those contacts are important for us," he said.

Abdullah welcomed Russia's announcement Monday of support for the Rabbani government and its forces, but he said there had been no explicit offer of U.S. support.

"The international community has ignored the situation in Afghanistan for so long. We are fighting against forces that are against the people of Afghanistan, and now the world has decided to fight against them. And so we are not only fighting our own enemies but against the enemies of humanity as a whole," Abdullah said.

Abdullah said he had intelligence showing that several bin Laden bodyguards were in Jalalabad, east of Kabul, on Tuesday. But there was no information about where bin Laden was.