Ministers have poured cold water on reports the Government has drawn-up a graduated plan to start easing the coronavirus lockdown within weeks.

Chancellor of the Duchy of Lancaster Michael Gove denied suggestions a “traffic light” strategy is about to be brought in which would see some schools and businesses allowed to reopen in mid-May.

Education Secretary Gavin Williamson also dismissed the Mail on Sunday report, tweeting: “No decision has been made on when we will reopen schools.

“I can reassure schools and parents that they will only reopen when the scientific advice indicates it is the right time to do so.”

Mr Gove told Sky News’s Sophy Ridge on Sunday: “It is the case that we are looking at all of the evidence, but we have set some tests which need to be passed before we can think of easing restrictions in this lockdown.

“It is entirely understandable, of course, that there should be a public debate about how we approach these difficult choices.”

Mr Gove also strongly defended Boris Johnson after a wide-ranging report in The Sunday Times claimed the Prime Minister had missed five meetings of the key Cobra committee in the run-up to the outbreak.

The report also stated a number of opportunities had been missed by the Government in January, February and March to try and lessen the impact of the gathering crisis.

Controversy has raged over the lack of personal protective equipment (PPE) for NHS staff, and low levels of testing as the disease took hold.

Mr Gove said: “The idea that the Prime Minister skipped meetings that were vital to our response to the coronavirus, I think is grotesque.

“The Prime Minister took all the major decisions.

“Nobody can say that the Prime Minister wasn’t throwing heart and soul into fighting this virus. His leadership has been clear.

“He’s been inspirational at times.”

Shadow health secretary Jonathan Ashworth later argued that Mr Gove’s line that one or two aspects of The Sunday Times story were off beam is “possibly the weakest rebuttal of a detailed expose in British political history”.

He told Sky’s Sophy Ridge on Sunday: “There are serious questions as to why the Prime Minister skipped five Cobra meetings throughout February, when the whole world could see how serious this was becoming.

“And we know that serious mistakes have been made, we know that our front-line NHS staff don’t have the PPE, that they’ve been told this weekend that they won’t necessarily have the gowns which are vital to keep them safe. We know that our testing capacity is not at the level that is needed.

“We know that the ventilators that many hospitals have received are the wrong types of ventilators and there are big questions as to whether we went into this lockdown too slowly, and now we hear the Prime Minister missed five meetings at the start of this outbreak. It suggests that early on he was missing in action.”

Sir Jeremy Farrar, a member of the Government’s Scientific Advisory Group for Emergencies (Sage), said he was “optimistic” about finding a vaccine for the Covid-19 coronavirus with advances in science.

But he acknowledged “the truth is we don’t have another vaccine for any other human coronavirus” and said finding a safe and effective treatment for the latest strain was “not a given”.

He told Sky News’s Sophy Ridge On Sunday: “I hope we would have a vaccine towards the end of this year – but that’s a vaccine in a vial, it’s a vaccine that we believe to be safe, a vaccine we think might be effective.

“I think it’s crucial to realise having a vaccine in itself, in say a million doses, which you know to be safe and you believe to be effective. That is not the end game.

“The end game is making sure that it is truly effective. It’s effective in the elderly, effective in young children, effective right across the age group in all populations.

“And then you have to manufacture that in billions of doses to administer them to the world.

“That is an enormous scientific challenge, it’s also an enormous logistics and delivery challenge.”

Niall Dickson, chief executive of the NHS Confederation, said a shipment of PPE that is due to arrive in the country is “a few days’ supply” and “may be enough to avert an absolute crisis over this weekend”, but added that “it doesn’t solve the longer term problem”.

Meanwhile, speaking about Mr Johnson’s health following his treatment for coronavirus, Mr Gove said: “The Prime Minister is recovering well. He’s in cheerful spirits.

“He had the opportunity to talk to Dominic Raab, his deputy, the First Secretary of State, on Friday.

“And the Prime Minister’s instructions to the rest of us in Government were communicated by the First Secretary of State when we had a conference call yesterday morning.”

Mr Johnson was treated for Covid-19 in intensive care at St Thomas’ Hospital in London earlier this month and is now recuperating at his country estate Chequers.