The German manufacturer has been in talks with the seven-time champion for weeks now as they look to extend their partnership beyond the end of this season.
Recently, both Mercedes and Hamilton expressed some optimism that a deal could get across the line imminently with several meetings to discuss the matter having been arranged.
However, still nothing has been signed and Mercedes boss Toto Wolff said at the Austrian Grand Prix that there would be no further developments before the British Grand Prix.
The delays have fuelled speculation that there could be key roadblocks in the deal, and even that there is the possibility of talks collapsing and both parties going their separate ways.
But Wolff has played down such suggestions and says that the contract is only taking so long because there is a desire to tidy up some final details.
“We want to do it super, to every detail, and sometimes you can have a situation where everything is carved out,” he explained.
“But this is not a money discussion at all. It is about the future, it is: what is it that we want to do right and optimise.
“We're not talking anything anymore about duration, money all of that. It is just other topics.”
The uncertainty about Hamilton’s future at Mercedes came against the backdrop of driver and team not seeing eye-to-eye at all times during the Austrian Grand Prix.
Hamilton voiced his dismay at track limits and the performance of his Mercedes W14 through the race, which reached a level where Wolff himself had to intervene and tell Hamilton to “drive the car.”
While some interpreted Wolff’s message as a sign of tension, he has dismissed such a notion.
“You should hear us talking on the phone and meeting each other,” he said. “That is nothing!
“I think we've had a bad spell of a weekend, all of us in the team, and that just makes us stronger.”
Wolff said that he felt he had to get involved in the matter because Mercedes was already battling through a difficult weekend and didn’t need to waste any opportunities in the race.
“We had a lot of discussion about track limits and whether they were enforced or not,” he said about Hamilton’s radio traffic.
“I felt that I wanted to just make sure that we were getting the best out of a package that didn't perform, and just give it the best shot that we have.”
