Cologne, Germany -- Germany's main Muslim groups cut their links to Germany's only professor of Islamic religion, charging that Muhammad Kalisch had questioned the existence of the Prophet Muhammad and Muslim beliefs about the origin of the Koran.

Kalisch teaches at the University of Muenster in northern Germany.

The four main Muslim groups had been represented on a board of advisors to his Center for Islamic Religious Studies (CRS) since the chair was established but there has been friction over his academic publications.

In a joint statement in Cologne on Friday, the council of Muslim organizations said it was concerned at the "discrepancy between fundamentals of Islamic teaching and the published positions of the head of the CRS."

Ayyub Axel Koehler, a German Muslim who is president of one group, the Central Council of Muslims, told DPA that "Kalisch calls fundamental teachings into question in such a stark way that it's not possible to go along with him."

He said Kalisch had questioned whether the Prophet really existed and what Muslims believed about the Koran's origin.

"We support the freedom of scholarship and teaching and we have no wish to gag him," said Koehler. "But we cannot advise people to learn from him."

In a response published by the university, Kalisch said he regretted the decision of the Muslim organizations.

"A university is not there to teach the content of faith, nor to approve the opinions of a professor as correct," he said. "Rather, the task of a university is to conduct independent, open-ended research." He said a university should equip students "to reflect critically and achieve intellectual independence."

An estimated 3.3 million people of Muslim faith live in Germany, 1.8 million of them Turks. Several German universities have faculties of Christian theology.

DPA/Expatica