Lord Coe has described allegations of widespread doping in athletics as a “declaration of war” and says it is time to “come out fighting” to protect the sport’s reputation.

The Sunday Times published data from 5,000 athletes, which it says reveals an “extraordinary extent of cheating”. Athletics’ world governing body, the IAAF, said the blood results were not positive tests or proof of doping.

“The fightback has to start here,” said Coe, an IAAF vice-president. “It is a declaration of war on my sport. There is nothing in our history of competence and integrity in drug testing that warrants this kind of attack.”