Des Moines, Iowa – Iowa Attorney General Tom Miller said Tuesday that Gov. Kim Reynolds has blocked his request to join a lawsuit that seeks to prevent changes to the U.S. Postal Service that Democrats claim could threaten mail-in voting.

Miller said in a news release that he wanted to join the lawsuit planned by more than 20 states that seeks to stop budget cuts and operational changes that are disrupting mail deliveries. Postmaster General Louis DeJoy said Tuesday he would delay some operational changes but the states plan to move ahead with the lawsuit and House Speaker Nancy Pelosi was pushing for legislation to block the postmaster’s actions.

DeJoy, a Republican donor and strong supporter of President Donald Trump, has implemented changes at the Postal Service at a time when the president has claimed without evidence that mail voting is vulnerable to fraud. Record numbers of voters are expected to vote by mail this fall due to the possibility of being infected with the coronavirus at polling places.

“I’m very concerned about service and policy changes at the Post Office,” Miller said in a statement. “Reports from the American Postal Workers Union indicate that mail delivery in Iowa has been slowed by limits on staff overtime and removal of automatic sorting machines.”

Miller, a Democrat, sought the Republican governor’s consent under a deal the two officials agreed to last year, after the GOP-controlled Legislature approved a bill that would have prevented the attorney general from joining any multistate lawsuits unless requested by the governor or Legislature. Reynolds agreed to veto the bill if Miller promised to seek her approval before joining any multistate lawsuits.

A spokesman for Reynolds didn’t immediately respond to a request for comment about the governor’s decision.