Mercedes boss Toto Wolff has claimed that he is only "99%" sure whether his driver lineup will remain the same in 2015.
The Silver Arrows have recently secured the long-term future of Nico Rosberg, but Lewis Hamilton's name is one of a number linked with a drive in McLaren's Honda-powered car when the Japanese manufacturer returns to the sport from next season.
However, while Wolff was unable to confirm whether both racers will remain with the constructors' championship leaders, the German appeared to be relaxed regarding negotiations over the Briton's future.
He told Sport Bild: "You have to hold something back because exceptional circumstances can always arise. In life, nothing is ever 100% for sure.
"On both sides we had the desire and decided to postpone the issue [Hamilton contract talks], because the championship is so intense.
"Rather than be discussing commercial issues, we want to get to the end of the season. And then the first thing we will do is sit down with Lewis and hopefully everything will be in the bag for the years after 2015."
Hamilton leads the drivers' championship by just three points heading into this weekend's Japanese Grand Prix at Suzuka.
