Renault have refused to comment on swingeing criticisms of their management from Mercedes motorsport boss Toto Wolff.
The Austrian said a team had gone back on their word to sign Mercedes-contracted Esteban Ocon, who looks like ending up without a seat next year.
Wolff did not name Renault, but they are the team he was referring to.
Wolff blamed “politics, hidden agendas and lies” for Ocon losing out on a the seat to Red Bull’s Daniel Ricciardo.
He added, talking to Sky: “In July, (Ocon) had two offers on the table with contracts and it was just a case of choosing the right one and he ended up not having any any more because people just simply don’t have the balls to stick to what they say.
“But it is no problem, we have to sort it out with Esteban. He is a strong guy, he has been through difficult moments in his career and we will fix this one as well.”
Wolff was negotiating in July with Renault and McLaren over a seat for Ocon in 2019.
Both were possibilities but Wolff chose Renault as the best option, and had agreed a deal for them to take the 21-year-old Frenchman.
But Renault are understood to have not told Mercedes that they were still in talks with Ricciardo, so Wolff was surprised when the French team signed the Australian.
McLaren had by then already decided to go for Carlos Sainz, who is driving for Renault this season, and are promoting their reserve driver Lando Norris, an 18-year-old Briton, into their other car.
Ocon now looks to be out of a drive for next season.
His Force India seat is to go to Lance Stroll, who drives for Williams this year, following the takeover of the team by a consortium of businessmen led by his father Lawrence, a Canadian billionaire.
Haas are understood to be sticking with Romain Grosjean and Kevin Magnussen, while Sauber have already signed Kimi Raikkonen and will have either Ferrari development driver Antonio Giovinazzi or incumbent Marcus Ericsson.
Williams are not keen on taking a Mercedes-contracted driver and Mercedes are not willing to let Ocon go.
“Not in a million years,” Wolff said, “because one day he is going to be in a Mercedes and win races and championships and show all the others out there that they made a mistake.”
Mercedes have Lewis Hamilton under contract until the end of 2020, while his team-mate Valtteri Bottas is only contracted until the end of 2019.
Ocon is likely to be a Mercedes reserve driver in F1 next year and Wolff will be left with a choice between him and Bottas for the second seat in the factory team in 2020.