Christian Horner believes there must be a "fundamental" difference between Lewis Hamilton's contract demands and what his Mercedes team is willing to offer.
The seven-time world champion's renewal talks have become the saga of the Formula 1 season so far. What was once seen as a formality has dragged out for longer than anyone anticipated.
Before last month's Canadian Grand Prix, Mercedes chief Toto Wolff suggested an agreement could be "days" away. But that turned out not to be the case.
Asked for his thoughts on the the situation, Red Bull team principal Horner believes there must be an important point upon which the two sides disagree and have so far been unwilling to budge.
"It's strange because we keep being told, and I keep seeing in the media, that it's just a matter of days," he told TalkSPORT. "That's been going on since February! So one can only assume that there is something fundamental that they can't agree on.
"We don't tend to conduct negotiations through the media. It is usually a couple of conversations around the table, and the job is done. So I don't understand why. There has to be something preventing it happening."
Both Hamilton and Wolff insist, though, that the main details of the contract have been agreed and that there are only side issues left to be resolved. "They want to do it super, to every detail and sometimes you can have a situation where everything is carved out," said the Austrian.
"This is not a money discussion at all. It is about the future, what is it that we want to do right and optimise? We're not talking anything anymore about duration, money, all of that – it's other topics."
And Hamilton replied: "That's correct," when asked about that statement at Silverstone on Thursday. Asked whether Mercedes' poor form had made him reconsider a new deal, Hamilton added: "That's not what I'm thinking.
"Before the end of the season we'll be already well into the contract. I still have 100 per cent faith in this team. I'm hoping to be here a lot longer. I feel like I've got another five years in me at least, no? Let's see."
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