LONDON (Reuters) - Formula One's governing body formally approved rule changes on Wednesday that will allow sole supplier Pirelli to carry out more testing of next year's wider tyres during the season.
Pirelli, who last October were awarded a new three-year contract from 2017, had warned that they might otherwise have to leave the sport.
The International Automobile Federation (FIA) said the World Motor Sport Council, its supreme body, had passed a measure agreed earlier in the week by the Formula One commission that includes all the teams.
"The changes will allow 25 car days of testing with current cars, fitted with 2017 tyre sizes, in 2016, 2017 and 2018," the FIA said in a statement.
"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."
Pirelli's motorsport director Paul Hembery was quoted after Sunday's Chinese Grand Prix as saying the testing agreement had to be approved this week.
"We cannot do our job without this (agreement being approved). We cannot deliver. We are being asked to make very significant changes, by changing the driveability of the tyres," he had told the motorsport.com website.
Formula One is preparing for major rule changes next season aimed at making cars faster, harder to drive and with more downforce. That will mean tyres being subjected to heavier loading and faster cornering speeds.
Teams are currently subject to strict limits on track testing before and during the season but the regulations had allowed for 12 days of tyre testing.
(Reporting by Alan Baldwin, editing by Ken Ferris)