The International Brotherhood of Teamsters, the only union among the nation's top 10 that hasn't endorsed Vice President Kamala Harris in her 2024 faceoff with former President Trump, could make an announcement later this week on whom they're backing in the White House race.

"We are going to look at any and all options, and I can’t commit to what we’re going to do," Teamsters General President Sean O'Brien told reporters at the union's national headquarters in the nation's capital.

O'Brien spoke after he and other Teamsters leaders met behind closed doors with Harris on Monday for a roundtable discussion.

The vice president didn't speak with reporters as she departed the Teamsters headquarters after making her pitch, as the Democrats' presidential nominee works to maintain her party's traditional high level of support from organized labor.

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Kamala Harris hits the ground running after her debate with Trump

Vice President Kamala Harris speaks during a campaign rally at Bojangles Coliseum, in Charlotte, North Carolina, on Thursday, Sept. 12, 2024. (AP Photo/Jacquelyn Martin)

O’Brien late last year announced the union’s first-ever interview process for their 2024 presidential endorsement and invited the major party candidates to make their cases.

The Teamsters met earlier this year with Trump and separately with President Biden, whom Harris succeeded atop the Democrats' national ticket two months ago.

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O'Brien made history in July as he became the first Teamsters president to address a Republican National Convention.

But his speech also sparked controversy, as he drew the ire of some other top Teamsters leaders and some of the rank-and-file membership. Democrats didn't invite O'Brien to address their convention last month in Chicago.

Republican National Convention

General President of the International Brotherhood of Teamsters Sean O'Brien speaks during the Republican National Convention in Milwaukee, Wisconsin, July 15, 2024. (Andrew Caballero-Reynolds/AFP via Getty Images)

O'Brien said on Monday that the Teamsters are finishing up their polling of the union's membership ahead of an executive board meeting on Wednesday, and added that the results of the polling would be publicly released.

He said the endorsement is "going to come down to the rank and file members, the polling and also the discussion and deliberation of the general executive board."

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"There’s no secret that the Teamsters union is very different than most unions, and I mean that with total respect; we represent everybody from airline pilots and zookeepers, O’Brien noted. "We don’t just represent registered Democrats, we represent registered Republicans and independents, and so we have to take [that] into consideration."

"We need to make sure we make the right decisions," he emphasized. "Our sole focus is representing those workers, negotiating strong contracts and organizing new members."

O’Brien said the Teamsters asked the same questions of Harris that they did of Biden earlier this year and noted that the president and vice president gave similar answers. 

"There wasn’t a whole lot of difference," he said.

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The Teamsters have asked the presidential candidates about their support for the PRO Act, a sweeping set of union-friendly changes to federal labor law, as well as where they stand on bankruptcy reform and antitrust policies.

Biden made history as the first sitting president to join striking workers on a picket line, and O'Brien highlighted that Biden has been "great for unions."

Trump in Las Vegas

Former President Trump arrives at Harry Reid International Airport after a campaign trip, Saturday, Sept.14, 2024, in Las Vegas. (AP Photo/Alex Brandon)

O'Brien also reiterated his criticism of Trump's recent comments in an interview with billionaire business mogul Elon Musk – when the former president praised the tech CEO for retaliating against striking workers by firing them – which is illegal.

Asked if Trump's comments would impact the Teamsters endorsement, O'Brien said "it plays into the decision."

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