The chances of a compromise deal being reached to head off the threat of a Formula 1 breakaway series will become clear in Paris tomorrow, when Max Mosley comes face-to-face with Ferrari president Luca di Montezemolo at a hearing of the FIA's World Motor Sport Council.
With the teams adamant that the ball is now in the FIA's court to react to the plans of the Formula One Teams' Association (FOTA) to set up its own series, AUTOSPORT understands that the stance adopted by both FOTA chairman di Montezemolo and Mosley in Wednesday's meeting will define where the sport goes from here.
FOTA is due to meet on Thursday to start pushing the green light on its calendar, regulations and the appointment of media and commercial promoters - showing that it is serious in its intention to press on with the new championship.
However, there remains the possibility that a deal can be reached to bring the FIA, F1 and the teams back into the same championship - although the governing body will almost certainly need to express its willingness to do so tomorrow.
One factor is, of course, whether or not FIA president Mosley chooses to stand for re-election in October, or if he honours the vow he made last year to stand down when his current term comes to an end.
Mosley's decision on that front now appears to rest on whether he and members of the FIA perceive that the F1 teams are not launching an all-out attack on the governing body.
Sources within the WMSC have suggested that their biggest concern at the moment is not the way Mosley has handled the current situation, but that the FIA's authority is being targeted by the teams. That much was made clear in the letter that Mosley sent to the FIA today.
Should the stance of di Montezemolo in the WMSC hearing convince the members and Mosley that it is not the FIA's authority as such that FOTA wants to change, then that, along with a compromise deal being reached in time, could be enough to encourage Mosley to stand aside in October.
An all-out assault on the governing body would almost certainly encourage Mosley to stand again.
What has become clear since the announcement of the breakaway plans on Thursday night is that the teams are not going to go out of their way to get the FIA back around a table to discuss a compromise.
It is very much up to the FIA to come up with ideas to push forward some sort of deal, which is why the FIA not yet pushed the green light on threatened legal action against Ferrari and FOTA for the breakaway plans. It could do so, however, if the teams' stance is aggressive tomorrow.
Brawn CEO Nick Fry said at the weekend that all eyes were on the WMSC meeting.
"The FIA meeting on Wednesday is critical to what happens," he said. "The teams have very clearly stated how they see the future - we have entered the championship with conditions and the question now is whether those conditions will be fulfilled. The ball is in the court of the FIA and we hope that there is a balanced discussion at the world council on Wednesday."
McLaren team principal Martin Whitmarsh said, however, the teams were wholly focused on what they were up to, rather than waiting for the FIA to act.
When asked how important he viewed Wednesday's meeting to be, Whitmarsh said: "It is not important to FOTA because our agenda isn't there, our agenda is to work out the way in which we go motor racing in the future. The WMSC meeting is an FIA meeting."
Whitmarsh reckons also that it was important the FIA and the teams moved on from the 'loony' comments made by Max Mosley at the weekend.
"I think that is why, certainly for McLaren, we are not saying any of those things and we are not responding to them either," he explained. "I think there is a lot of emotion and ego, and that is one of the issues that perhaps is an impediment to making progress and working together.
"Hopefully we will keep our egos in check at McLaren and, if all the other parties do that, I hope we can have an environment where we can work together."
Despite the stand-off by the teams and the FIA, senior figures within the sport remain upbeat that a resolution can be found.
Former world champion Williams is one of only two current teams that has lodged an unconditional entry to the 2010 championship, but its technical director Sam Michael said he was eyeing some sort of compromise deal.
"From our point of view we are hopeful there will be some sort of solution where everybody is racing in the same championship," he told AUTOSPORT. "Williams' position is very clear, as we have made clear in the public domain. Hopefully there will be some common sense in the next few days.
"Ultimately there will be common sense and the teams will all be racing in the same championship. You could also say that we are probably in the best position because we are just busy getting on with what we do, which is making racing cars.
"Sometimes when you get involved in political situations you can end up getting so wrapped up in it, you can't see the wood for the trees. That's not really happened to Williams because the option wasn't there for us. There wasn't really a choice to make, we were contracted and that was it.
"It's not like we sat there and said, 'ooh shall we go with this group or that group'. It was absolutely clear, not just by regulation, but contractual law that we had to do what we did."