The idea of replacing the most outspoken driver in Formula One – Mark Webber – with one who is about as loquacious as a Trappist monk – Kimi Raikkonen – would appeal to the mischievous humour that bubbles inside Christian Horner.

But the Red Bull team principal was wearing his most serious countenance when the scenario was put to him at Claridge's – after all, there are few things more serious than afternoon tea at the most quintessentially English of hotels.

Webber's contract is up for renewal. It always is, for since becoming half of the most successful partnership in the F1 paddock, with Sebastian Vettel, he has operated on a one-year deal.

Unthinkable though it may be for fans of this popular anglophile, who has lived in England for most of his professional life and won two of the last three races at Silverstone, this weekend's British Grand Prix could be his last outing at the famous old airfield in Northamptonshire.

The Australian will be 38 next year and has not been a championship contender since 2010, while his relationship with Vettel – which even at the best of times appeared similar to that between Punch and Judy – has been even more strained this season; the smart money says he won't be at the Milton Keynes-based team next year.

The 33-year-old Raikkonen, the world champion of 2007 who has been outstanding since making a comeback with Lotus last year, would be the obvious replacement and Horner did not demur. But the independently-minded Raikkonen had problems when he drove for big teams – Ferrari and McLaren – before finding a happy home at Lotus. The suspicion lingers that those issues may resurface should he join another leading team.

Horner does not agree. "Red Bull is a great environment for any driver," he said. "Perhaps it's a bit more relaxed than some of the more corporate teams. Any driver would enjoy that environment. Our focus is to get the best out of them as drivers and athletes and not bog them down with clutter. Any decisions we would make will be made on the merit of the driver."

Horner says he is not necessarily looking to split a partnership that has delivered three straight constructors' championships, in which time Vettel has picked up a hat-trick of titles. "Mark has contributed a huge amount. Without his points we wouldn't have won any of the three constructors' world championships. He's won nine grands prix for us so far. All his podiums bar one have come in a Red Bull car.

"He's a hard worker. He's worked very well with the technical team. The problem for him is that his team-mate has been somebody pretty special. And so week in week out he's being measured against a driver that is pretty underrated.

"With Mark it's always been very straightforward. We've agreed year-on-year deals with him as we did with David Coulthard at a similar stage in his career.

"First of all, we need to sit down and discuss the situation with Mark. He's done a great job for the team he joined in 2007 and before making any decision it's important to understand what his intentions are. We've only completed seven races. It's still pretty early in the year."

Webber and Vettel, though never close on a personal level, have usually maintained a professional working relationship. But there has been that unmistakable whiff of decree nisi around the pair since the Malaysian Grand Prix in March, when Vettel – who has just signed a new contract – ignored team orders and deprived leader Webber of a well deserved victory.

Horner added: "There is a professional relationship but there's nothing beyond that between them. They both know what they're employed by the team to do and there are no pretences."

When Vettel was asked about Webber, he said: "I respect him very much as a driver. I think he is very quick. He has certain very, very strong areas where I am struggling to match him and to beat him, such as around Barcelona in the last sector.

"I am not really keen on talking about Malaysia. I respected Mark a lot before that and I still respect him after that. We never had a fight and we have never screamed at each other. We always treat each other with respect and that's the relationship I have had since I joined."

Horner says it is Vettel's mental strength that impresses him most. "He's totally insular in terms of his focus and concentration," he said. "He doesn't allow anything to distract him. Like all great sportsmen, when the pressure points come that's when you see them rise to the challenge. And on each occasion Sebastian has done that, whether it's Abu Dhabi in 2010 or Brazil last year, or Abu Dhabi again last year. He has a mental resilience that marks him out compared with some of his rivals."

Vettel said: "I think some part is experience and certain routine, but maybe I'm just not clever enough to think what could go wrong. In Abu Dhabi in 2010 [when he won the last race of the season to take his first title] we had a strategy meet before the race.

"Certain numbers were flying around about the percentage of Fernando [Alonso], Lewis [Hamilton] and Mark [Webber] scoring so many points, and I wasn't really paying attention because it wasn't what we should have done.

"Normally when you prepare for a race it's what you think is the best to do and just because you are in a special situation doesn't really require special actions because if it would, then it just means your normal system is quite bad and you haven't really thought what you need to do."

When asked whether he felt he was underrated by Alonso and Hamilton, he said: "Well, I'm not relying on their opinion." He also said he did not know how many points his main rivals had in the world championship.

Horner might be able to replace Webber but he will never find another Sebastian Vettel.