Formula One tyre suppliers Pirelli will be able to use 25 car days of testing to prepare for the 2017 season after governing body the FIA formally ratified changes to the sporting regulations.
A meeting of the World Motor Sport Council on Wednesday approved a plan aimed at giving Pirelli additional dates to prepare their tyres for next year.
Proposed regulation changes mean tyre dimensions are set to widen from 2017, with the front tyres due to go from 245mm to 350mm diameter, and the rears from 325mm to 405mm.
A full statement from the FIA read: "The World Motor Sport Council today approved changes to Articles 10.2 and 10.6 of the Formula One Sporting Regulations in order to provide the appointed tyre supplier additional opportunities to undertake testing in preparation for the 2017 season.
"The further testing was deemed to be essential for the purpose of developing the new tyre sizes permitted by the 2017 F1 Technical Regulations.
"The changes will allow 25 car days of testing with current cars, fitted with 2017 tyre sizes, in 2016, 2017 and 2018.
"In addition, there will be an opportunity to test prototype 2017 tyres (in 2016 sizes) on 2013 or 2014 cars – these tests on older cars only apply in 2016."
