A court is to hear damning claims that a German engineer played a key role in an international nuclear trafficking gang set up by Pakistani scientist Abdul Qadir Khan, the news magazine Der Spiegel said Saturday.

It said the allegations were made by Gerhard Wisser, a German businessman living in Johannesburg, South Africa, as part of a plea bargain last year to reduce charges over his own role in the ring.

Spiegel said Wisser had admitted meeting twice with the engineer, currently on trial in the German city of Stuttgart over his alleged role in efforts to export uranium-enrichment equipment to Libya so that the Arab nation could make its own nuclear weapons.

The ring, which was broken up in 2003, is also suspected of selling nuclear technology to North Korea and Iran.

In the admission to high court in Pretoria, Wisser had said he had been personally commissioned by the German engineer to build part of the equipment in South Africa, the magazine is set to report in its issue appearing Monday.

The businessman had received blueprints at meetings in July 1999 in Dubai and in February 2000 in Zurich, Switzerland. (dpa)