Major tyre issues detected after the first day of running at the Qatar Grand Prix have forced the FIA into a number of changes for the remainder of the weekend.
Analysis by Pirelli following first practice discovered a "separation in the sidewalls between the topping compound and the carcass cords" on "many of the tyres" scrutinised.
It is believes that the aggressive kerbs at the Lusail International Circuit have triggered the issue, leading to the changes for the remainder of the event.
An FIA statement read: "Following the standard analysis of tyres used during Free Practice 1 yesterday, in which tyres that have been used for approximately 20 laps are examined by Pirelli to check various safety parameters, a separation in the sidewall between the topping compound and the carcass cords on many of tyres that were checked was discovered.
"It is the view of the FIA and Pirelli that a significant number of additional laps on these tyres could result in circumferential damage of the tyres with subsequent air loss, and tyres analysed with lower lap numbers showed a much-reduced extent of the issue.
"This issue has likely been caused by the high-frequency interference between the tyre sidewall and the 50mm ‘pyramid’ kerbs used extensively at this circuit, aggravated by the propensity to ride those kerbs."
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A number of measures have been taken by the FIA for the rest of the event, including a revision of track limits at Turns 12 and 13.
As such, there will be a '10-minute familiarisation session' for drivers to reacclimatise to the new track limits. This will begin at 16:00 local time, meaning a 20-minute delay to Sprint Shootout.
Further analysis will be carried out following the 19-lap Sprint race to decide whether action will be needed ahead of the Grand Prix.
If the problem does persist, a directive will be issued that dictates tyre life must not exceed 20 laps for new tyres used in the race,
The number would rise to 22 for any used tyres fitted in the race in order to account for in and out laps in qualifying.
This measure would oblige a minimum three-stop strategy for all drivers.
The statement continued: "Pirelli and the FIA will carry out extensive research and simulations in order to establish with complete confidence the reasons behind this issue, and to work on solutions to avoid it in the future."