Pirelli finalises plans for 2021 F1 tyre test at Portuguese GP

The test is the Italian company's only chance to do any track running ahead of a possible tweak to next year's tyre specifications.

Governing body the FIA has already agreed to run the current tyres unchanged for a third season in 2021, and has mandated a downforce cut of around 10% in order to reduce loadings.

However, Pirelli still hopes to introduce a construction update if the Algarve test proves successful, with a deadline on a decision set for 1 November.

With no testing possible outside race weekends the sporting regulations were modified this year to allow the first 30 minutes of an FP2 session to be used for prototype running, with all drivers obliged to participate.

"The target is trying to develop a tyre with a higher level of integrity," said Pirelli F1 boss Mario Isola when asked by Autosport.

"Which means that we can use it at a lower pressure.

"This together with a reduction in downforce that is planned for next year is helping the tyre to work in a better way, and therefore reduce the overheating.

"It cannot be a complete new product as we only have the chance to test the prototypes in Portimao, that is also a new track, and a track that's been resurfaced."

Each team will have three sets of tyres for the 30-minute test, with one driver running two sets, and the other only one.

"We are planning to bring three sets of tyres per teams, which means 30 sets of prototypes," Isola added.

"That doesn't mean 30 different prototypes - we will have probably something in the range of 8-10.

"I don't want to give you the exact number, simply because the test is blind for the teams, and any information I release means that the teams are making calculations.

"We are going to provide the run plans to the teams. In general they are going to run the same number of laps on both cars.

"The approach is to run one car on a back-to-back, and one car on a long run, within the 30 minutes, so it's not very long.

"The plan is that the car that is running the back-to-back has a baseline and a prototype, and the other car has one set for the long run.

"We have to work in a way that is trying to preserve the sporting equity. We cannot give to one team 10 prototypes to test, and to another one and that's all.

"So we are trying to do this plan in a fair way."