During scrutineering at Silverstone on Thursday, damage was found to a wheel tether on Sainz's car. And although a request was made for it to be replaced, the team refused.

With the FIA deeming that the damage made the car unsafe, Toro Rosso has been asked to explain itself.

A note from the FIA technical department said: "During initial scrutineering car number 55 was found to have a damaged wheel tether. The scrutineers made the team Scuderia Toro Rosso aware of this and asked the team to replace it.

"The team refused to follow the instructions of the scrutineers and therefore the technical delegate checked the damaged tether himself and found that the tether was not only damaged but also several cut fibres were knotted together.

"Therefore the team was aware of the damaged tether and presented the car in an unsafe condition for scrutineering."

The attempt by Toro Rosso to enter the car is also a breach of Article 12.1.1.b of the FIA's International Sporting Code, which states it is an offence to enter a car that is known to be 'ineligible'.