An appeal to the US Supreme Court against a lawsuit accusing major international companies of aiding South Africa's previous apartheid system has fallen on a technicality, so the case will now proceed.

Amongst the companies targeted by the suit are BP, Exxon Mobil, Citigroup, Deutsche Bank, General Motors and Ford. The plaintiffs are seeking damages of more than $400bn, arguing that the companies broke international law by assisting the apartheid regime in South Africa.