COLUMBUS (AP) — A group of drug retailers and distributors is asking an Ohio federal appeals court to remove the judge overseeing national opioid litigation after the judge himself denied their requests.

Walmart, Walgreens, CVS, Rite Aid and drug distributors AmerisourceBergen, McKesson and Cardinal Health told the 6th U.S. Circuit Court of Appeals in a filing Tuesday that Cleveland-based U.S. District Judge Dan Polster is not impartial.

Polster made the initial ruling on their claim, declining Thursday to remove himself from the massive multi-district litigation. More than 2,000 cities and counties are seeking damages from pharmaceutical manufacturers and distributors over the national opioid crisis.

The latest in the dispute over Polster’s fitness to preside over the case comes less than three weeks before the first jury trial is set to begin.