WASHINGTON — President Trump signed an executive order on Thursday to set up a commission to study his unproven allegations of voter fraud in last year's presidential election, as he continues to grapple with the fallout from his abrupt and controversial firing of FBI Director James Comey.

The commission will be chaired by Vice President Pence, who will be joined by up to 15 other members appointed by the president. Kansas Secretary of State Kris Kobach – who has advocated for some of the most restrictive voting laws in the nation – will serve as the commission's vice chair.

"The Commission will review policies and practices that enhance or undermine the American people's confidence in the integrity of federal elections — including improper registrations, improper voting, fraudulent registrations, fraudulent voting, and voting suppression," the White House said in a statement.

Trump, who lost the popular vote to Democrat Hillary Clinton by nearly 2.9 million votes, has claimed that last year's election included up to 3 million to 5 million fraudulent voters — but there is no evidence to back this assertion.

Trump's executive order creating the "Presidential Advisory Commission on Election Integrity'' comes as Democrats and other critics accuse him of firing Comey to obstruct an ongoing investigation into possible collusion between Trump campaign associates and Russians who tried to influence last year's election.

The president is planning a visit to the FBI headquarters in the coming days to calm the waters, administration officials said. But the unexpected announcement of the new commission — which was not on Trump's public schedule for the day — might be seen as a way to distract from the firestorm unleashed by the Comey firing earlier this week.

As voting rights advocates blasted the new executive order, federal and state election officials from both parties are also disputing Trump's claims of massive voter fraud. They say there have been few, if any, incidents of people voting when they were not registered – or voting by people who were not American citizens.

"Every election is going to have issues, but I don’t think that three to five million people voting illegally was one of those issues," said Thomas Hicks, then-chairman of the federal Election Assistance Commission said in January in USA TODAY.

Election officials have said they worry Trump’s claims could shake the faith of voters, particularly at a time when the FBI and Congress are investigating whether Russia interfered in last year’s presidential election.

For his part, Trump has stood by his claim.

"We'll see after the committee," Trump told Time magazine in March. Trump had originally been expected to sign the executive order creating the voter commission in late January, but it has been consistently been put off.

The advisory commission will hold public meetings and meet with federal state and local officials, as well as election experts, according to the order. The commission will present a report to the president.

Voting rights advocates came out swinging against the new order.

“We hold grave concerns about this commission and the impact that it will likely have on minority communities across our country," said Kristen Clarke, president and executive director of the Lawyers’ Committee for Civil Rights Under Law. “In our view President Trump has launched this commission to create a distraction from actual threats to our democracy, including ongoing voter discrimination, voter suppression and Russia’s interference in the 2016 election.”

Michael Waldman, president of the Brennan Center for Justice at New York University School of Law, called the commission “a sham and a distraction.’’

Brennan released a recent national report that disputed Trump's claims of massive fraud. Of the 23.5 million votes cast in last year's general election, about 30 were incidents of suspected of noncitizen voting, the report found.

"All studies, including our own, have shown that voter fraud is vanishingly rare,'' Myrna Pérez, deputy director of the Democracy Program, said in a statement. "And, the myth of voter fraud has been the justification for restrictive voting laws for years, serving to roll back access to our democracy for people all across the country.”

Voting rights advocates say the administration should focus on making access to the polls easier instead of unfounded claims of voter fraud. They argue some lawmakers are using the claim to ramp up more restrictive election laws.

States, mostly controlled by Republican legislatures, have adopted more election laws, including voter ID, in recent years. Supporters say they help protect against voter fraud.

Voting rights advocates also took aim at Trump's decision to appoint Kobach to the commission, who has pushed some of the nation's most restrictive election laws.

“No commission with Secretary Kobach at the helm can be taken seriously," Clarke said.

Clarke called the commission a waste of taxpayer's money.

“There is no need to focus on vote fraud given the fact that there is no evidence to substantiate claims that vote fraud exist on any significant level in our country," she said. “It’s also disappointing that nowhere in this executive order… is there any sensitivity to this administration’s obligation to enforce federal rights law. There is no reference to voting discrimination or voter suppression. Those words simply do not appear."

Rep. Cedric Richmond, D-La., chairman of the Congressional Black Caucus, called the commission a waste of taxpayer money.

"Instead of supporting an investigation into fake issues like voter fraud that pose no threat to the country, the Trump Administration should support an investigation into real issues that do – real issues like Russian interference in the 2016 presidential election, campaign collusion and cover-up, and voter suppression and intimidation,'' Richmond said in a joint statement with and Michigan Rep. John Conyers, the top Democrat on the House Judiciary Committee.

Trump's order, however, could get support from some Republican lawmakers, who have welcomed a federal investigation into allegations of voter fraud.

“Safeguarding our democracy requires fair and accurate elections,” Rep. Gregg Harper, R-Miss., chairman of the House Administration Committee, which has jurisdiction over federal elections, said earlier this year.