South African activists have launched a lawsuit against 20 European and American firms for allegedly encouraging human rights abuses in South Africa by trading under the apartheid regime.

This is the second major corporate suit relating to apartheid, following success in claiming damages from companies for their activities during the Nazi holocaust.

The corporations listed in the complaint include Swiss banks Credit Suisse and UBS, oil firms Exxon Mobil and BP, car makers Ford and General Motors, and computer giant IBM.

The lawsuit was filed in a New York court "on behalf of victims of state-sanctioned torture, murder, rape, arbitrary detention and inhumane treatment", by the Khulumani support group and Jubilee South Africa.

No damages are specified, although cases relating to the holocaust have netted settlements valued in the billions of dollars.

Stout defence

This case is the second of its kind.

In August, US lawyer Ed Fagan sued another group of firms - including many of the same companies - which he said helped finance the apartheid regime.

That case, which was asking for reparations of some $100bn (�63bn), is not yet settled.

Responding to the latest lawsuit, UBS said it would defend itself "vigorously".

"UBS completely rejects the groundless and unjustified claims," UBS president Peter Wuffli said.

"We regret what happened in South Africa during the times of the apartheid regime," Mr Wuffli added, but insisted that there was no connection between the bank's activities and the suffering of South Africans.