An election official in Wisconsin has resigned, saying he lost the backing of fellow Republicans because of his refusal to support former President Donald Trump's false claims of fraud in the 2020 presidential election.

The announcement by Wisconsin Elections Commission member Dean Knudson, a Republican, creates more uncertainty as the embattled panel plans to elect a chairman ahead of competitive congressional and gubernatorial elections in November.

"It's become clear to me that I cannot be effective in my role of representing Republicans on the commission," Knudson said at a Wednesday meeting of the bipartisan commission, which oversees elections in the Midwestern industrial state.

Trump lost Wisconsin by nearly 21,000 votes in 2020, but many Republican officials and candidates in the state have refused to acknowledge Trump's defeat despite multiple recounts and a state audit affirming the result. Several Republican candidates have called for abolishing the commission.

Knudson's replacement will be selected by Wisconsin Assembly Speaker Robin Vos, a Republican who ordered an investigation of the 2020 election despite scant evidence of fraud. However, Vos also has acknowledged Democrat Joe Biden's victory in the state.

Vos did not immediately respond to a request for comment.

Trump has pressed fellow Republicans to continue challenging his 2020 election defeat, even though lawsuits, recounts and audits have not uncovered any evidence of fraud.

He has not always been successful: Republican primary voters in Georgia on Tuesday rejected several high-profile candidates who put those claims front and center.