The Prime Minister’s father has brushed off criticism of the Government’s handling of the coronavirus crisis, saying it has been “on the right track” in dealing with the pandemic.

Stanley Johnson, in a wide-ranging interview with Ta Nea, a Greek daily newspaper, also argued the over-70s should not all have to face tougher shielding measures.

He also claimed to have predicted nearly 40 years ago that there could be a deadly virus.

There are no clear answers and I think we are probably on the right track

Mr Johnson, speaking from his home in Exmoor, south-west England, told the newspaper: “We are living in a time of great uncertainty and nobody quite knows what the impact is or what the disease is or what to do.

“At the moment there are no clear answers and I think we are probably on the right track. We have been taking a tough line here and we’ll have to see how that goes.”

Criticism of the response to Covid-19 by Boris Johnson’s Government has ranged from fears of a lack of PPE for frontline workers to the number of deaths in care homes, but Mr Johnson said of his son: “I didn’t notice that he’s received a lot of criticism; it doesn’t seem to me (that he has).”

Asked about his son’s battle with coronavirus, which included a stay in intensive care, he said he “felt as any father must feel when his son is at death’s door”.

Mr Johnson has landed a book deal to reissue a thriller novel from 1982 he wrote about a mysterious virus and one man’s fight to stop a deadly pandemic.

Originally titled The Marburg Virus, it is now to be called The Virus and is being released as the world grapples with the Covid-19 pandemic.

He said: “Yes, I predicted this outbreak. I was working in Brussels at the time and I’d already written four thrillers by then. The Marburg Virus was my fifth thriller, which was based on a visit I made to that small town in Germany which in 1967 had a tremendous outbreak of a disease.”

Mr Johnson believes the pandemic could herald a “greener way of life”.

He said: “Speaking as an environmentalist which I have been for many years, I can imagine that this dreadful happening, the spread of the coronavirus, will give us a chance when we come out of it to rethink some of our patterns of production and consumption. I think we will see a big push now towards a greener way of life.”

Mr Johnson, who turns 80 in August, advised against any plan for tougher safety measures for the over-70s, who are often thought of as vulnerable.

He told the newspaper: “I don’t want to see measures taken which discriminate against one particular sector of the population.

“For example the elderly, anyone over 70, will have to stay put, when everybody else can move around. I don’t think that’s the right thing to do. We, the elderly, have certainly played our part.

“I don’t think you can say to one section of the population ‘you’ve got to bear a particular brunt’ while others don’t.”

Any plans to visit his Villa Irene holiday home in Pelion, central Greece, will probably have to be scrapped.

He said: “I’m very worried that we may not be able to do it this summer. This is a worry to me.

“We are in this country in lockdown and even if we can leave Britain it’s not clear to me that we would yet be welcome in Greece. I don’t know. But of course I’d love to be there, even if had to go and self-isolate in my house I’d do that.”