Teamsters International, which represents more than 1.3 million workers, declined to endorse a candidate ahead of the November presidential election, but released data showing that most members backed Donald Trump over Kamala Harris.

The union’s decision not to endorse for the first time in nearly three decades comes amid investigations into President Sean O’Brien, who became the first Teamsters leader to speak at the Republican National Convention in July. Teamsters Vice President John Palmer called the decision to appear at the convention “unreasonable” given Trump’s anti-union record.

Harris, the Democratic presidential candidate, met with the Teamsters this week for a roundtable discussion ahead of the vote. Trump and Joe Biden attended a roundtable discussion with the union earlier this year.

“Unfortunately, neither major candidate was able to make any meaningful commitments to our union to ensure that the interests of working people are always put before big business,” O’Brien said in a statement Wednesday. “We asked both Trump and Harris for commitments not to interfere with critical union campaigns or core Teamsters industries — and to respect our members’ right to strike — but were unable to secure those commitments.”

Polls released by the union before the announcement showed its members supporting Biden over Trump. However, more recent surveys by the union showed members supporting Trump over Harris.

The Teamsters National Black Caucus endorsed Harris last month.

In response to the denial of support, Teamsters Against Trump, a grassroots group of Teamster members and retirees, announced that they will expand campaign efforts to get Vice President Kamala Harris elected.

On September 18, the California Teamsters also came out in support of Harris, in response to the lack of support from Teamsters International.

“When it comes to my vote for president, as a proud Teamster, there is no contest. Donald Trump doesn’t give a damn about the working class. As president, Trump didn’t lift a finger to help Teamsters whose pensions were in jeopardy. Instead, he installed his billionaire cronies in the White House and did everything he could to prevent workers from organizing into unions,” James Larkin, a member of Teamsters Local 299 in Detroit, Michigan, and a member of the group, said in a statement.