Nigeria could seek as much as $3.5 billion in damages from Royal Dutch Shell and Eni over an allegedly corrupt deal for one of Africa’s biggest untapped oilfields.

The Federal Republic of Nigeria has filed a claim in the High Court in London against the two oil companies over the deal in which they acquired the OPL 245 oil licence for $1.3 billion. It alleges that the deal was corrupt and resulted in Nigeria receiving “no or negligible value” for rights to the “extremely valuable” offshore licence, which it estimates was in fact worth “at least $3.5 billion”.

Of the $1.3 billion that was paid, Nigeria says it ended up receiving about $200 million, with up to $1.1 billion being swiftly transferred on to other…