Mercedes boss Toto Wolff admits that the potential downsides for his team of a future engine partnership with Red Bull are still dominating his thoughts.
Red Bull has set its sights on landing a Mercedes customer engine contract for 2016, and wants to get out of the final year of its contract with Renault.
Matters are expected to move on quickly, with Renault closing in on a final decision about its long term strategy for F1 as it ponders the return of a works effort.
But although there are suggestions Mercedes' senior road car management can see the attraction of tapping into the exposure and new marketing opportunities offered by a Red Bull partnership, it is also clear that there are fears it could open the door to the team knocking the German car manufacturer off the top of the grid.
Speaking at Brisighella in Italy where, on behalf of his Mercedes team, Wolff collected the Lorenzo Bandini Trophy, he said he was cautious about the Red Bull situation.
"If I judge it from the perspective of our team, it is an agreement that you should not do," said Wolff.
"Our car and our successes are the result of hard work and huge investment from Daimler.
"We built our supremacy, while today there is a team that has decided that they do not want to stay with their partners. It is a different philosophy to ours.
"Nothing has happened yet, because we do not look so much at the possible benefits of the deal, as to the negative arguments that are likely to be more for our team."
Engine situation complicated
The 2016 engine situation should become clearer as soon as Renault has announced what its long-term plan in F1 is. That could come as early as this weekend.
Mercedes may ultimately feel that a supply deal with Manor – which is evaluating its engine options for 2016 – may be better in not risking damaging its own success in F1.
It could also open the door for a race seat for Mercedes reserve driver Pascal Wehrlein, who the German car manufacturer wants to be competing in F1 next season.
Interview by Franco Nugnes