EASING the national lockdown too fast would risk a disaster, a government scientist warned Boris Johnson today, ahead of next week’s unveiling of a “road map” for lifting coronavirus restrictions.

Dame Angela McLean, a member of the government’s Scientific Advisory Group for Emergencies (Sage), urged caution, as many vulnerable people have yet to have the Covid-19 vaccine.

The Prime Minister is to set out on Monday how the lockdown rules will be eased, and is under pressure from Tory backbenchers to throw off all the shackles.

He has claimed that his government’s strategy would be based on a “cautious and prudent approach,” but Dame Angela, who also serves as chief scientific officer at the Ministry of Defence (MoD), said the country “got into real trouble” last year for “not [being] cautious enough.”

She told MPs of the Commons’ science and technology committee that while numbers of cases, hospitalisations and deaths were falling, “we still stand with a high number of infections.” 

Dame Angela said: “I think we can say very, very clearly: Don’t unlock too fast, because if you unlock a lot while a lot of the most vulnerable are still unvaccinated, genuinely, we risk disaster, frankly.

“I think none of us want a situation where there is a wave of infection mostly amongst people who are not terribly [vulnerable] but that spills over into deaths and very serious illness that is very focused on some bits of society.

“I’m not being gloomy, I’m being cautious. I think it is correct to be optimistic and cautious.”

In response to her comments, Mr Johnson told reporters: “I do think that’s absolutely right.”

On a visit to Wales today, he said discussions will continue with leaders of devolved nations over whether they will leave lockdown at the same time. 

Mr Johnson said: “I know there’s a lot of understandable speculation in the papers and people coming up with theories about what we’re going to do, what we’re going to say, and about the rates of infection, and so on.

“I would just advise everybody: just wait, we’ll try and say as much as we can on that.”

Earlier, NHS Providers head Chris Hopson suggested the number of current coronavirus infections needs to drop to below 50,000 before Mr Johnson could consider easing the national measures.

The most recent figures show that 695,400 people in England had Covid-19 in the week ending February 6.