Williams director Patrick Head has told McLaren to forget about Nico Rosberg becoming Fernando Alonso's replacement for next season.
Hamilton (right) and Rosberg both drove in the GP2 series before F1
Lewis Hamilton had tipped the Williams driver as one of three men he could see stepping into Alonso's shoes.
But Head responded: "Nico is contracted to our team for 2008 and we have an option for his services for 2009.
"We plan to go into next season with Nico as our lead driver and we would not entertain a McLaren approach."
When asked who would be alongside him next season, Hamilton said: "(Nico) Rosberg, (Adrian) Sutil or (Heikki) Kovalainen.
"The most important thing is that he is a team player," added the Briton, whose sensational first season in F1 led to him falling out with Spaniard Alonso.
They are all fantastic drivers and I know them quite well - if I could choose I honestly don't know who I would pick
The double world champion left McLaren on Friday after agreeing a release from the last two years of his deal.
Rosberg, the son of Finland's 1982 world champion Keke, is under contract with Williams and Head added in the Mail on Sunday: "McLaren are a team in a position to offer very large salaries, but our aim is to be looking to strengthen Williams."
Rosberg finished ninth in the 2007 drivers' championship, while Finland's Kovalainen took seventh, boosted by his second place in the Japanese GP.
Renault chief Flavio Briatore said on Saturday that he had offered Alonso a deal to return to the team where he won the 2005 and 2006 titles.
Sutil is a friend of Hamilton's and drove for F1 minnows Spyker in 2007 but is highly rated.
Spyker were sold to Indian tycoon Vijay Mallya in October and will become Force India F1 next season.
Mallya said recently: "I am very happy with Adrian Sutil and I've told team boss Colin Kolles that we need to keep him."
McLaren are determined to pick the right man to partner Hamilton after he and Alonso's feuding contributed to the duo losing out in the drivers' title race to Ferrari's Kimi Raikkonen by one point.
Speaking at a Mercedes 'Stars and Cars' event in Stuttgart, Hamilton, 22, added of Rosberg, Sutil and Kovaleinen: "They are all fantastic drivers.
"I know all of them quite well, and if I could choose I honestly don't know who I would pick."
And Head had a mischievous suggestion of his own.
"What about McLaren bringing Michael Schumacher out of retirement?" he said.
"Michael's still fit - and probably bored. I suspect he has found sitting on the pit wall dull."
Also at the Mercedes event, McLaren's double world champion Mika Hakkinen announced he was retiring from racing in the German Touring Car series.
Hakkinen, 39, who won 20 Grands Prix in his career, said he would continue to be involved with Mercedes off the track.