The International Brotherhood of Teamsters announced Wednesday that it would not officially endorse any candidate in the 2024 presidential election, ending months of speculation about whether the union would support Republican Donald Trump or Democrat Kamala Harris.

The union’s executive board said in a statement that polls among its members showed no majority support for Harris and no general support for Trump.

“The Teamsters thank all candidates for meeting face-to-face with members during our unprecedented roundtable discussions. Unfortunately, none of the major candidates were able to make serious commitments to our union to ensure that the interests of working people are always put ahead of those of big business,” Teamsters President Sean O’Brien said in the statement.

“We have demanded commitments from both Trump and Harris not to interfere in key union campaigns or core Teamsters industries – and to respect our members’ right to strike – but we have not been able to achieve those commitments,” O’Brien said.

With 1.3 million members, the Teamsters union is one of the largest unions in the country. The non-support is a break from the union’s decades-long tradition of supporting Democratic candidates. But it’s not a total surprise.

In July, O’Brien indicated in a speech on the first night of the Republican National Convention that the union was ready to support Trump.

“As the strongest and most democratic union in America, it was critical for our members to move this endorsement process forward. Democrats, Republicans and independents are proud to call our union home, and we have a duty to represent and respect each and every one of them,” O’Brien said.

“We strongly encourage all of our members to vote in the upcoming elections and continue to participate in the political process. However, this year no presidential candidate has received the endorsement of the Teamsters’ International Union.”

In a national poll of Teamsters members conducted after the Sept. 10 presidential debate, union members overwhelmingly (58 percent) supported Trump and opposed Harris, according to results released by the union ahead of its formal statement of support.

The Trump campaign team cited the poll results in its response to the union’s lack of support, writing in a campaign email that “the Teamsters union base supports Donald Trump for president.”

The latest results are very different from polls conducted when President Joe Biden was still the Democratic nominee. Before Biden dropped out of the race on July 21, rank-and-file union members supported Biden over Trump by 44.3% to 36.3%.

The announcement came just days after union members and leadership met with Harris, who had received support from several other unions.

Union leaders were also prominently featured at the Democratic National Convention in August, but the Teamsters — and O’Brien — were conspicuously absent. After his appearance at the convention, a union spokesperson confirmed to CNBC that O’Brien had not received an invitation to speak at the Democratic National Convention.

“The vice president’s strong track record of union work is why local Teamsters across the country have already expressed their support for her – along with the overwhelming majority of unions,” Harris campaign spokeswoman Lauren Hitt said in response to the union’s decision.

If Harris is elected president, “she will take care of the members of the Teamsters union no matter what happens – because they always have and always will fight for her,” Hitt said.

This is a developing story, please check back later for updates.