The Teamsters will not back either Harris or Trump in the 2024 presidential election.

• The Teamsters union has decided not to endorse a candidate in the 2024 presidential election, putting an end to months of speculation about their choice between Donald Trump and Kamala Harris.
• The union has deviated from its longstanding practice of supporting Democratic candidates by not endorsing a candidate in the upcoming election.
• In July, O'Brien signaled that the union was considering endorsing Trump when he spoke at the first night of the Republican National Convention.

The Teamsters union has decided not to endorse a candidate in the 2024 presidential election, putting an end to months of speculation about their choice between Donald Trump and Kamala Harris.

The General Executive Board of the union stated that a poll of its members showed no majority support for Harris and no universal support for Trump.

Teamsters President Sean O'Brien expressed gratitude to all candidates who met with members during the unprecedented roundtables. However, he stated that neither major candidate made serious commitments to the union to prioritize the interests of working people over Big Business.

O'Brien stated that they tried to obtain commitments from Trump and Harris to refrain from meddling in crucial union campaigns and respecting the right of Teamsters members to strike, but were unsuccessful in doing so.

The Teamsters union, with 1.3 million members, is one of the largest labor groups in the country. However, the non-endorsement of a Democratic candidate marks a departure from the union's long-standing tradition of supporting Democrats.

In July, O'Brien announced that the union was considering endorsing Trump after he spoke at the first night of the Republican National Convention.

Our union, being the strongest and most democratic in America, it was crucial for our members to drive the endorsement process. We have members from different political backgrounds, including Democrats, Republicans, and Independents, and we must represent and respect each one of them, O'Brien stated.

"The Teamsters' International Union has not endorsed any candidate for President in the upcoming election."

According to the union, in a national survey of Teamsters members conducted after the Sept. 10 presidential debate, 58% of union members backed Trump over Harris, while 31% supported Harris.

The Trump campaign used poll results to argue that the majority of Teamsters Union members back Trump for president in their response to the union's lack of endorsement.

The most recent polls show a stark contrast to the results of surveys conducted prior to President Joe Biden's withdrawal from the race on July 21, with Biden receiving 44.3% support from union members compared to Trump's 36.3%.

Union members and leadership met with Harris, who received endorsements from other labor unions, shortly before the announcement was made.

Despite being present at the Democratic National Convention in August, the Teamsters and O'Brien were noticeably absent. A spokesperson for the union later confirmed to CNBC that O'Brien had not received an invitation to speak at the convention.

The Harris campaign did not immediately respond to a CNBC request for comment.

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