KABUL, Afghanistan — Afghanistan ordered hundreds of South Korean Christians to leave the country, accusing them yesterday of seeking to undermine its Islamic culture.

The group’s leader, Choi Han-woo, denied that the 1,200 South Koreans, who had gathered in Afghanistan for relief work and a cultural festival, took part in any religious activities.

An Interior Ministry spokesman, Yousef Stanezai, said the Koreans entered the country with tourist visas but that their activities showed they had a different agenda.

“The program was against the Islamic culture and customs of Afghans,” he said, adding that the South Koreans had been told to leave the country as soon as possible.

The accusations came amid increasing intolerance and violence against foreign troops in Afghanistan, a crackdown in the capital on drinking and prostitution linked to foreign influences, and the recent announcement of a plan to reinstate the Vice and Virtues Ministry, which enforced its harsh version of Islamic morality under the ousted Taliban government.

Representatives of the group and the ministry were negotiating yesterday over the schedule for their deportation, a spokesman for the group, Sung Han Kang, said. Mr. Kang said the group, a nongovernmental organization called the Institute of Asian Culture and Development, had a Christian background but was not trying to win converts.