Samir Nasri believes the greatest threat to Manchester City's chances of retaining their Premier League title come from Chelsea and Manchester United, but not Liverpool.

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City finished 22 points ahead of their neighbours last season and are already four points clear of them as United await their first win under Louis van Gaal.

But midfielder Nasri, who was also a champion in 2012, thinks they can feature prominently in the title race. He told City's matchday programme: "I think our two main rivals will be Chelsea and Manchester United.

Nasri believes Chelsea and Man United will be City's closest title rivals and doubts Liverpool's chances. Lindsey Parnaby/AFP/Getty Images

"Chelsea have made some good signings and Cesc Fabregas will be the guy to replace Frank Lampard. He is a great player, I know that because I was with him at Arsenal.

"Chelsea had a weakness up front last year but have signed Diego Costa. They will be really dangerous.

"United have a new coach, have strengthened as well and don't have any European competition -- so I expect them to come back stronger, too."

Nasri is more worried about United than his former club Arsenal, though he added: "But Arsenal could be in there, too, and bringing in players like Alexis Sanchez will make them stronger."