SINGAPORE (AFP) - Mercedes team principal Toto Wolff on Friday (Sept 14) launched an extraordinary attack on fellow Formula One bosses for their "lies" which have left Esteban Ocon without a drive next season.

Two months ago, Ocon had received provisional deals to sign for either Renault or McLaren after Force India were taken over by Canadian billionaire Lawrence Stroll, who will replace the French 21-year-old with his son Lance.

But Renault instead made a surprise swoop for Red Bull's Daniel Ricciardo after Carlos Sainz left to replace Fernando Alonso at McLaren.

That meant both doors had been slammed shut on the Mercedes-backed junior driver Ocon, who now looks almost certain to be squeezed out of Formula One in 2019.

"What has been going on this year in July and August was just unbelievable," fumed Mercedes chief Wolff.

"There was so much politics in the background, hidden agendas and lies," an angry Wolff told British television channel Sky F1 at the Singapore Grand Prix.

"Not all of the good kids are going to be in cars next year and Esteban will probably be one of them.

"In July he had two offers on the table and it was just a case of choosing which one was the right one. Then he ended up without anything because people simply don't have the [courage] to stick to what they say."

Ocon told reporters in Singapore it was difficult to accept the fact he may not be in Formula One next season.

"It's hard to believe I was in a great position two months ago and things have gone that way now," the Force India driver said on Thursday.

"I worked really hard to get here and this year I think I progressed compared to last year," added Ocon, who qualified in third place for last month's Belgian Grand Prix.

Only Haas, Sauber, Toro Rosso and Williams are yet to finalise both drivers for next season meaning Ocon's hopes of a seat are dwindling.

"I'm fighting hard to do the best I can every race," Ocon said in the Singapore paddock.

"Driving here not knowing what I will do next year, it's hard to swallow."