Russian rookie Nikita Mazepin accused Haas team mate Mick Schumacher of "cheeky" behaviour at the Dutch Grand Prix on Saturday and said the German had shown his true nature by breaking an agreement.
Schumacher, son of Ferrari great and seven times world champion Michael, suggested the Russian was making a drama out of nothing and he had been cleared to pass Mazepin before his final run.
The spat was another headache for team boss Guenther Steiner, with Haas bottom of the standings and yet to score a point this season.
Schumacher is a protege of engine partner Ferrari while Mazepin's billionaire businessman father is the team's title sponsor.
Both drivers were summoned to stewards after qualifying for blocking Aston Martin's Sebastian Vettel in the first phase, and were eventually cleared of wrongdoing.
Mazepin had already publicly blamed his team mate by then, however.
"He overtook, backed me up, and put me into Seb. I'll have a word with the team to see why that happened," he told Sky Sports television.
Speaking to reporters later, the Russian felt Schumacher had overturned a team agreement and wrecked his qualifying lap "on purpose".
"I know my place in the team. I've got a team boss and I am more than happy to follow the rules because I think it's very important to be a team. One day the rules will play towards you, one day the rules will play against you," he said.
"What I don't like with people is when they are cheeky, fighting for P19 (19th place). I think it just shows their true nature and I don't tolerate that."
Schumacher, speaking separately to reporters, recognised Mazepin was "quite vocal about things in the press."
Steiner said it would not be the last time the drivers disagreed.
"It's difficult, especially this year with fighting at the back. Your only fight is with your team mate, in our case at the moment.
"So obviously it is a little bit more heated, because the only thing you can win is the team mates' battle."