The United Nations refused to send negotiators to Afghanistan on Monday after the Taliban religious army rejected the team's leader, jeopardizing a multimillion-dollar aid program.

Also Monday, the alliance that opposes the Taliban reported fighting around the Ghorband Valley, 35 miles north of the Afghan capital, Kabul. The opposition accused the Taliban of initiating Monday's battle.The United Nations has substantially reduced aid to the parts of Afghanistan controlled by the Tali-ban and halted aid in the north because fighting within the opposition alliance has made conditions unsafe for U.N. workers.

"Basically we are in limbo right now," while negotiations on keeping the U.N. team leader proceed, said Sarah Russell, a U.N. spokeswoman in Pakistan.

Taliban officials have refused to say why Alfredo Witchi-Cestari, the U.N. coordinator for humanitarian aid to Afghanistan, was not welcome. They would not grant him a visa.

The United Nations has said it will not even open talks unless the Taliban allow Witchi-Cestari to lead the team.

At risk are millions of dollars in programs, ranging from helping refugees return from neighboring Pakistan to removing land mines to reducing one of the world's largest poppy-growing areas, which supply the opium used to make heroin.

Witchi-Cestari ordered a temporary suspension of U.N. aid to southern Afghanistan this month to protest attacks on its staff by the Taliban governor. The United Nations also has protested several Taliban edicts, particularly those directed at women.

Washington's ambassador to the United Nations, Bill Richardson, met with Taliban officials last week. He said they were ready to meet with U.N. representatives and seek a compromise between U.N. demands and the Taliban's interpretation of Islam.