Gold Reserve Ltd has asked an American appeals court to halt the court-supervised sale of shares in Citgo Petroleum’s American parent company, alleging that the process has been tainted by undisclosed conflicts of interest involving two of the sale’s key advisers.

In a petition filed this week with the United States Court of Appeals for the Third Circuit, the Canadian-based miner — one of several creditors pursuing Venezuela’s state-owned oil company, Petroleos de Venezuela SA — claims that law firm Weil, Gotshal & Manges and investment bank Evercore have ongoing financial ties to Elliott Investment Management and certain PDVSA bondholders who stand to benefit from the sale.

According to the filing, Weil and Evercore have earned more than $170 million in fees from those clients since being appointed to advise the court-appointed Special Master overseeing the auction. Gold Reserve argues the connections create “an intolerable appearance of bias” in favour of a lower-priced Elliott-backed bid that the Special Master has recommended for approval.

Gold Reserve maintains its own bid for the shares of PDV Holding Inc, the American parent of Citgo, was $2 billion higher and should prevail under Delaware law, which requires that attached assets be sold to the highest bidder for the benefit of recognised judgment creditors.

The company’s petition asks the appeals court to order a temporary stay of the sale until the Delaware District Court rules on Gold Reserve’s motion to disqualify the Special Master, his advisers and the presiding judge from further involvement in the case. Without intervention, Gold Reserve says, the sale could close as soon as December 1, leaving no opportunity to challenge what it calls a tainted process.

The dispute is the latest twist in a complex effort to satisfy billions of dollars in international arbitration awards against the Bolivarian Republic of Venezuela, whose state assets — including Citgo, a major American refiner — have become the focus of competing creditor claims.

The Third Circuit has not yet ruled on Gold Reserve’s emergency petition.