Billionaire Mark Cuban clarified his suggestion on Friday that Charles and David H. Koch once tried to pay Donald Trump to leave the presidential race, saying there had been a serious “buyout” attempt, just not from the Republican financiers.

The claim arose on Hillary Clinton’s Boeing 737 aboard a flight to a rally here in Detroit when Cuban, one of the campaign’s biggest surrogates, came to the press cabin to take questions alongside chairman John Podesta. Earlier in the day, appearing with the candidate at an event in his hometown of Pittsburgh, Cuban told the crowd they shouldn’t trust a President Trump to say no to a bribe of billions of dollars to act on behalf of foreign governments.

Later, as Clinton’s plane made its way to Detroit, a reporter joked that the Koch brothers, two of the party’s wealthiest Trump critics, could’ve “bribed” the nominee to drop out.

“They tried,” Cuban snapped back.

“They did?” the reporter asked.