Sole tire supplier Pirelli has warned that it could walk away from Formula One after the current season if the sport fails to ratify tire testing plans by close of play on Monday.

The website motorsport.com quoted Pirelli motorsport director Paul Hembery as saying there would not be enough time to prepare new, wider tires planned for 2017 if the governing body's F1 commission were to stall in approving rule changes.

Pirelli won a tender for the 2017-19 contract in October, but that has yet to be signed off with the International Automobile Federation (FIA) due to the testing issues.

"When I land [in Europe ­after the Chinese Grand Prix], if I don't have an e-mail confirming it's approved, or something else positive, then you will be calling me for a different story," said Hembery.

"This is it. We cannot do our job without this."

Motorsport.com said Pirelli had written to the FIA earlier in April to clearly state that it would withdraw from the 2017-19 contract if the test program was not resolved immediately.

The website said FIA race ­director Charlie Whiting had recently visited senior Pirelli representatives in Milan to push the testing agreement forward.

It added, however, that during the weekend's third round of the championship in Shanghai, an agreement had been reached for five teams to join a trial program to run from July for a period of 25 car days.

F1 is preparing for major rule changes next season aimed at making cars with more downforce, which are faster and harder to drive.

As part of the plans, wider tires will be 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 now allow for 12 days of tire testing.