Martin Whitmarsh insists that McLaren did what it could to retain the services of Lewis Hamilton before the Briton elected to make a move to Mercedes for 2013.

Hamilton's switch was confirmed on Friday to bring to an end the biggest story in the driver transfer market, with Sergio Perez being signed from Sauber as his replacement.

The deal means Hamilton's 14 year association with McLaren will end at the conclusion of the current season and Whitmarsh said the team had made the Briton a good offer that he has elected not to take up.

"What we have to do is acknowledge that we didn't agree terms with Lewis' management and acknowledge that for Lewis, McLaren has been a big chapter in his life," he told Sky Sports News. "He has been a big driver for this team but we now have to ensure that, after all the interest, we focus firmly on the final six races of the season, all of which we can win. Then we have to look towards an exciting future.

"We went a long way to make a good offer to Lewis but ultimately it takes two to get to a signature - and clearly we didn't agree terms and have moved in a different direction. Lewis is a great driver but has to make decisions about his life. We had lots of talks, went into lots of details and drew up lots of complex contracts. We negotiated lots of details and lots of freedom - it was a very good commercial offer that we made."

Speaking to the BBC, Whitmarsh then questioned if Hamilton's decision to move to Mercedes would turn out to be the right one.

"For anyone leaving McLaren, and [Hamilton] wants to win, I think that's a mistake because I have faith and belief in this team," said Whitmarsh.

"Whether you measure it over the last four races, four years or 40 years, we're a fantastic team.

"So I would say to any driver who wanted to win in this sport 'come and join McLaren and aspire to join McLaren'.

"I wouldn't advise anyone to leave McLaren if they want to win, but I've got to respect Lewis's decision and really wish him well."