The head of the International Brotherhood of Teamsters gave a surprising boost to former President Donald Trumps election effort on Monday, calling the GOP nominee one tough SOB in a speech at the Republican National Convention in Milwaukee.

Teamsters General President Sean OBrien did not endorse Trump for the White House but praised him as a politician not afraid to hear from new, loud, and often-critical voices. He said his union would happily work with a GOP administration if given the opportunity.

I refuse to keep doing the same things my predecessors did, OBrien said in a speech that at times criticized both Democrats and Republicans. Today the Teamsters are here to say we are not beholden to anyone or any party.

It was an unusual speech from a high-profile labor leader at the RNC.

Organized labor is a pillar of the Democratic Party and a crucial ally in President Joe Bidens reelection plans. Most major unions have denounced Trump due to his vehemently anti-union and anti-immigrant record in the White House.

OBrien had sought out the speaking invitation , upsetting Teamster members who back Biden. But he has defended the move as a bit of bipartisan political outreach. (OBrien also dined with Trump and posed for a thumbs-up photo with the former president back in January.)

He brushed off criticism from union members and other progressive allies in his address.

I dont care about getting criticized, he said. Its an honor to be the first Teamster in our 121-year history to address the Republican National Convention.

The union has not yet made an endorsement in the presidential race, though it formally backed Joe Biden in his first run against Trump in 2020.