Villeneuve: Mercedes should now favour Hamilton in F1 title fight

Hamilton closed the gap to F1 title rival Sebastian Vettel to just seven points with victory in the Belgian Grand Prix, while Bottas finished fifth and is 34 further adrift.

Ferrari already appears to be backing Vettel over Kimi Raikkonen in its pursuit of a first drivers' championship since the latter triumphed in 2007 and first constructors' title since 2008.

"Bottas is not on Lewis's level," Villeneuve told Autosport.

"He's not in the same game, he's not in the same group, it's obvious now."

When asked if it was time for Mercedes to consider favouring Hamilton, the Canadian said: "Yes, but Toto [Wolff, Mercedes team boss] doesn't want to do it.

"He's protecting Bottas right now, he's the one who put Bottas there.

"Bottas is his driver, even though he says he isn't the manager anymore, it's still his driver.

"He is protecting him because he still needs to get him a contract for next year.

"Yes [it is risking the title]. They have already [lost] the points from [Hungary, when Hamilton gave back a position to Bottas as part of a team arrangement], so they need to consider it."

Bottas said at Spa he understood Mercedes would need to back one driver at some stage, but felt it was still too early for the team to do so.

"For sure at some point I understand if the team wants to really go for the championship, really make sure that at least one of the guys wins it," he said.

"But it's a bit early.

"There's still eight races to go, that's a big amount of points."