Leading engineer Tim Goss has become the latest senior figure within the FIA to quit, in a role which oversees important technical matters in Formula 1.
Goss was appointed as Single-Seater Technical Director of motorsports governing body in 2021, following a 28-year stint at McLaren as their technical chief.
One of his key responsibilities was overseeing the current set of technical regulations introduced in 2022, and their implementation.
He was recently involved in the controversial technical directive introduced at the 2023 Singapore Grand Prix, which focused on the flexible bodywork.
Goss was reportedly dissatisfied with the state of affairs within the governing body and with the process leading up to the introduction of new F1 rules in 2026.
His departure follows that of Sporting Director Steve Nielsen, who will be replaced by Tim Malyon who has been the FIA's Safety Director since 2021.
FIA single-seater director Nikolas Tombazis said: "We are disappointed to lose a person of Tim's calibre from the organisation. Tim has played a major part in the technical department and has always operated to the highest level.
"We understand that his career is taking a new direction going forward and we support and respect his desire to pursue another path."
Malyon will oversee "all sporting matters, including race direction and the Remote Operations Centre in Geneva," with Niels Wittich remaining in his role as F1 race director.