Formula 1 will not feature 18-inch wheels as scheduled in 2021.
Because the new chassis rules have been delayed because of coronavirus, Pirelli boss Mario Isola confirmed that the 18-inch wheels will also not race next year.
"We are in the middle of the development for the 18-inch wheels," he told Auto Motor und Sport.
"But because the chassis rules will be postponed, we will continue with 13 inch next year. We are in daily contact with the FIA and still need to understand exactly what the plans for the future will look like."
However, Isola said it is possible the 2020-spec tyres will be developed somewhat for 2021.
"It just depends on whether we get any opportunities to test," he said. "Especially if we want to have a world championship in the second half of the year, I am not sure if there would be time.
"Without testing, I see no option than to continue with the current tyres."