Process & Industrial Developments, a firm based in the British Virgin Islands set up solely to build a gas processing plant in Nigeria, won a $6.6 billion arbitration award after the 2010 deal collapsed. The award has been accruing interest since 2013 and is now worth more than $9 billion.

Nigeria in September successfully sought the right to appeal an August ruling that would have converted the arbitration award to a judgment, which would make it easier for P&ID to seize its assets.

Nigeria has said it would fight making any kind of payment to P&ID. The country’s anti-graft unit has also charged two foreign nationals and a former petroleum ministry official with wrongdoing related to the case. P&ID has criticized the investigations as a “sham” that would “never pass muster” in other jurisdictions.

Nigerian Attorney General Abubakar Malami last week said the nation was appealing a requirement that it deposit $200 million with the court in order to secure a stay on asset seizures while it challenged the August ruling.

“This variation in security, which was proposed by Nigeria as an alternative solution during a procedural hearing on 22nd November, has been accepted by the court and P&ID,” the spokesman for the attorney general said in an emailed statement.

P&ID did not immediately respond to a request for comment.

The government has also expanded its legal team to include London-based law firm Mishcon de Reya. Shaistah Akhtar, a partner with the firm, will lead the legal team alongside Mark Howard QC of Brick Court Chambers, the spokesman said.