A former Governor of Delta State, Mr James Ibori has lost the bid to appeal his conviction by a UK court.
In a swift response, he has instructed his lawyers to file a case at the European court of human rights.
A UK court had convicted Mr Ibori and Bhadresh Gohil, his lawyer, of money laundering.
Mr Ibori, who served as Delta governor from 1999 to 2007, pleaded guilty to a 10-count charge of fraud involving sums amounting to at about $66 million.
He was slammed a 13-year jail term of which he served six years and returned to Nigeria in February 2017.
Mr Ibori had sought to appeal his 2012 conviction in a bid to upturn the ongoing trial to confiscate his assets.
He alleged misconduct by British police and prosecutors, which, he argued, tainted the judicial process.
However, an appeal court sitting on Wednesday struck out the ex-governors case.
The ruling will allow British prosecutors to resume efforts to confiscate tens of millions of dollars’ worth of assets and return them to Nigerian public coffers.
The assets have been frozen for years while the case has been dragging through the courts.