Formula E champion Sebastien Buemi will miss the New York double-header if its clash with the World Endurance Championship's Nurburgring round remains.
The 2017 WEC calendar was ratified by the FIA last month and confirmed the clash on the July 15-16 weekend.
Though he could lose up to 58 points in the FE title battle, Buemi told Autosport he would put any Toyota LMP1 commitments before his FE campaign with Renault e.dams.
"The decision is made," he said. "The priority is Toyota.
"As a driver I have to focus on my job.
"The best thing I can do is try to have a good season."
The clash happened because WEC boss Gerard Neveu has an agreement with his teams not to have a race within four weeks of the Le Mans 24 Hours, while the Nurburgring needed a two-week gap leading up to its proposed Formula 1 German Grand Prix date on July 30.
But the 2017 F1 calendar issued by the FIA last month lists Hockenheim as hosting the German GP for a second year in a row, raising hopes the clash can be avoided.
Buemi said he "can't believe there's no possibility to not have a clash" but pointed out the impact missing New York would have on his FE title bid would be determined by which of his fellow drivers were also absent.
His title rival from last season Lucas di Grassi told Autosport it was not clear which he would prioritise because he did not know what his 2017 programme would be.
The Brazilian drives for the Abt Audi Sport team in FE and has been a full-time member of the Audi LMP1 programme for the past three seasons.
He suggested he would choose whichever series he was performing better in because Audi's increased involvement in FE meant both now "have the same priority".
"Worst case scenario is you're fighting for both championships," said di Grassi, who is optimistic he will continue in WEC and FE.
"If I'm fighting for both titles we'll sit down with the team and discuss what I should do."
Venturi's Stephane Sarrazin (who drives the sister Toyota to Buemi's in the WEC), Dragon Racing driver Loic Duval (di Grassi's Audi team-mate) and DS Virgin Racing's Sam Bird (part of the Ferrari GTE Pro line-up) are the other FE drivers currently on a full-time WEC programme.
It is unknown what that trio of drivers will do.
Sarrazin, like Buemi, could miss the WEC race without Toyota needing to draft in a replacement as they could compete with two drivers.
Di Grassi and Duval share the #8 Audi with Oliver Jarvis so the German manufacturer would need to replace one of them, although it has several drivers with LMP1 experience racing in other categories.
Bird shares the #71 AF Corse Ferrari 488 GTE in WEC with Davide Rigon, so the Italian team would also need to find a substitute.