The London-based law firm which pursued the action against oil trading giant Trafigura over the alleged dumping of toxic waste in the Ivory Coast has claimed a record £105 million in costs.

The unprecedented figure, which Leigh Day & Co confirmed was correct, dwarfed the only known comparator - the BCCI litigation, Trafigura's QC Sean Wilken told the High Court. By contrast, he added, Trafigura's costs stood at £14 million.

Mr Wilken told Mr Justice MacDuff, who formally approved the confidential settlement of the largest ever group action last September, that if every claimant had been paid in full, that would amount to about £3 in costs for every £1 recovered. But he said that up to Easter, cheques had been cashed by 12,250 claimants - 41% of the total - and the process had stalled since the middle of March. He added that Leigh Day accepted that the costs were high.

Mr Wilken said: "In fact, we would say they are staggeringly high. I am told that this is one of the largest, if not the largest, costs claims in legal history.

"So we say this court is faced with groundbreaking claims of English lawyers in circumstances where the Ivorian claimants have not been paid in full the compensation which was supposedly the rationale of this litigation. Bluntly, we would like to know what happened to the money we paid to settle these claims."

It was later agreed between the two sides that issues raised should be dealt with by the senior High Court official who will assess costs at a further hearing at the end of this year.