Formula 2 organisers have announced that both races in Austria and Britain will begin behind the Safety Car, prior to a rolling start, amid ongoing issues with the new car's clutch.
Drivers have experienced issues with the clutch on the new-for-2018 car and several updates have been put in place, including at Spielberg this weekend, after further problems in France a week ago.
Drivers were given an extra 15-minute session on Friday morning in order to conduct practice starts and were also afforded an additional start following the conclusion of the usual practice session.
It was determined afterwards that series chiefs could not sufficiently guarantee that the issue had been addressed, and the next four races will start behind the Safety Car.
"Following issues experienced on the starting grid at Le Castellet where some cars stalled at the start, modifications were implemented to the starting procedure for this weekend at Spielberg," a statement read.
"A practice start session was added at the end of today’s Free Practice from which data was analysed. The Formula 2 organisers then provided the FIA with these data and conclusions to assess the appropriate way forward.
"As the 2018 F2 season is currently in the middle of a triple header where making validated changes is difficult, the FIA has decided that for safety reasons the Formula 2 formation laps of Rounds 6 and 7 at Spielberg and Silverstone will start behind the Safety Car and follow procedures set out in Article 39.16 of the F2 sporting regulations.
"The Safety Car will lead the grid at the start of the formation lap, complete one lap and return to the pit lane. During the lap the teams will be informed that there will be a rolling start and “RS” will be displayed on the track light panels. At this point, the lights on the Safety Car will be extinguished and the leader may dictate the pace. The race will start when the first car crosses the line."
Formula 2 boss Bruno Michel said: "This is not an ideal situation, but the drivers’ safety is a top priority. As we do not have the time to test and properly validate a permanent fix to the starting issues what the FIA has decided is definitely the safest decision.
“This will also give us enough time to work on a solution to the problem and return to a safe and normal situation for Budapest and the remaining of the season."
George Russell will lead the drivers away, having claimed pole position during Friday's qualifying session.
See also: F2 chiefs on 2018 technical issues
