Dr Hilary says starting the nationwide lockdown earlier would not have worked and has slammed the British public for "not taking it seriously".
Appearing on today's instalment of Good Morning Britain, the medical expert discussed with hosts Ben Shephard and Susanna Reid whether an earlier lockdown would have been more effective.
It comes after Professor Neil Ferguson said on Wednesday that putting the country into lockdown a week earlier could have saved thousands of lives.
Dr Hilary said he agrees with Professor Ferguson's estimation on the show earlier, but also warned that Brits would not have taken it seriously.
"I'm sure Professor Neil Ferguson is right," he said, while hitting out at the attitudes of those who attended Cheltenham Festival earlier this year.
"Had we put a lockdown in place across the country earlier, we would have saved lives," he continued.
"But it would have been extremely difficult to implement those measures at that time for various reasons. Look at the enthusiasm and look at the passion people had to go to Cheltenham Festival."
He added: "People were not listening to the advice being put out, you know, from scientists and doctors at the time. Nobody seemed to take it seriously."
