Martin Whitmarsh has admitted that he hopes to retain Lewis Hamilton in the long term, but says the deal is unlikely to be agreed over the summer break as suggested by the English driver.

"We've known Lewis a long time," said the Woking outfit's boss during the latest team phone-in. "We have been concentrating on the season and I think there has been more speculation, more concern and more interest about Lewis's situation in the media than there has been perhaps within the team or within Lewis's mind.

"We are often asked questions about it," he added, "but I don't think it occupies as much time in our minds as it does in column inches."

Asked if his team's recent drop in performance will play a part in Hamilton's decision making, Whitmarsh was adamant: "No," he replied, "I think we're going to the next two races to try and win, as we do with every race. I think Lewis is more intelligent than that and I hope the same applies to the media."

Asked about Hamilton's claim that the deal could be agreed over the forthcoming break, Whitmarsh insisted that there is no need to rush. "I don't think we should put any timeframe on it," he said. "I think it's something that's got to be determined for both parties preferably before the end of the season. I don't think there's any need to do so against any tight timeframe for that resolution."

Looking ahead to this weekend's German Grand Prix, Whitmarsh is confident that a raft of upgrades will put the team and its drivers back in the championship(s) hunt.

"The sidepods from the front to the rear are quite different so you'll notice those and there are other bits and pieces that the sharper-eyed will see," he revealed. "And clearly there are some parts which are hidden to the naked eye. So they are the main area of modifications and they will be reasonably noticeable.

"In terms of Silverstone, it was about getting the tyres to work and getting them at the right temperature and not graining. We had graining on the option tyre. On Lewis's car, for example, the first set of prime tyres were quite strong. Ten laps later we went on to the second set of prime tyres, with the same pressures, the same temperatures, the same preparation and by a lap and a half Lewis felt those tyres were significantly different to the first set he'd run quite successfully. It was difficult to interpret, unless it was higher tyre degradation. We obviously had a poor qualifying session. I think on the intermediate tyre we were reasonably competitive. Up until that point, on the dry tyre and the wet tyre I don't think we had enough temperature in the intermediate which was why we struggled in qualifying and the race thereafter was quite difficult.

"As you know Formula One changes very quickly," he continued, referring to the team's poor showing at Valencia and Silverstone. "Your fortunes can change from being very strong in Canada, which we clearly were, to a disappointing last couple of races. I think Silverstone was an unusual weekend. Our focus is always to keep developing the car.

"I think for everyone, not just McLaren, trying to understand how to work the tyres correctly is quite a substantial challenge. So eliminating mistakes, improving the performance of our car and understanding the tyres and seeing if we can exploit them better are all on the top of our to-do list."

Finally, the Englishman refused to confirm or deny speculation that a tie-in with Coca-Cola could be in the offing. "As you can imagine we don't talk about commercial discussions," he said. "We have enjoyed a good and very successful partnership with Vodafone. We will be with them for some time to come and we talk together about whether that would be lengthened beyond the existing length of the contract.

"There are also a whole range of other conversations with existing partners and new partners. But I'm sure you can imagine that we are quite unlikely to disclose those discussions."