The Italian marque had wanted to debut a new kevlar-belted tyre at Silverstone this weekend, but some teams objected against the fundamental change.
Jun.29 (GMM) Pirelli on Saturday insisted its rear delamination problems have not returned.
As a compromise, Pirelli is now fielding an identical specification tyre, but with a new sort of glue that should prevent the tread from separating from the carcass due to the overheating steel.
However, on Saturday, McLaren's Sergio Perez suffered a rear failure, triggering suggestions Pirelli has not succeeded in solving its problems.
But Paul Hembery insists: "A cut in the side of the tyre shoulder was to blame," he told Germany's Auto Motor und Sport.
The failure caused damage to the floor and rear wing of Perez's updated McLaren, but luckily the team had a spare wing in its luggage.
As for the floor, "Sergio will have to use the old (specification) for the rest of the weekend", a source is quoted as saying.