A leading Scottish scientist has suggested lives could have been saved if the UK Government had acted more quickly at the start of the coronavirus outbreak.

Sir Ian Boyd, a Professor of Biology at St Andrews University, who is a member of the SAGE group of science experts advising the Government, said he would have liked ministers to have acted "a week or two weeks earlier" in tackling the pandemic, claiming it would have “made quite a big difference" to the death rate.

He told the BBC’s Coronavirus Newscast: "Acting very early was really important and I would have loved to have seen us acting a week or two weeks earlier and it would have made quite a big difference to the steepness of the curve of infection and, therefore, the death rate.

"That's really the number one issue: could we have acted earlier? Were the signs there earlier on?"

Sir Ian explained how the Government had based its initial assessment on the Sars virus of 2003, another respiratory infection, which is less infectious than Covid-19. It is believed to have originated from cave-dwelling bats in China. It infected more than 8,400 people and killed almost 800. There is no vaccine for Sars.

Sir Ian claimed Britain and other European countries were a “bit slower off the mark" and less prepared than those countries, which had had experience of Sars more than a decade ago.

He said the Government would have been given "very blunt and very clear" advice from his colleagues Sir Patrick Valance, its Chief Scientific Adviser, and Prof Chris Whitty, its Chief Medical Officer.

"One could point the finger at ministers and politicians for not being willing to listen to scientific advice. You could point the finger at scientists for not actually being explicit enough.

"But at the end of the day all these interact with public opinion as well. And some politicians would have loved to have reacted earlier but in their political opinion it probably wasn't feasible because people wouldn't have perhaps responded in the way they eventually did."

Sir Ian, who was over eight years the Chief Scientific Adviser at the Department for the Environment, also urged ministers to stop saying they were "led" by the science.

“The statement 'we are guided by the science' is slightly misleading,” he declared. “I don't think ministers intend it to be misleading; they intend it to help to provide trust in what they are saying. And quite rightly so.

"Basically, what we in the scientific community do is give the best advice we can based on the evidence that's available to us. We then pass it to Government ministers and the policy parts of Government, who can then take that and do with it what they like within the policy context."

Earlier this week, Therese Coffey, the Work and Pensions Secretary, sparked a row after she suggested that if ministers had made mistakes early on this could have been down to “wrong” scientific advice. Downing St distanced itself from the Cabinet minister, insisting: “Advisers advise and ministers take the decisions.”

Meanwhile, another leading scientist claimed the UK had been "too much on the back foot" and needed clearer leadership during the coronavirus outbreak.

Sir Paul Nurse, Chief Executive of the Francis Crick Institute, said the country had been "increasingly playing catch-up" and scientists and politicians should lay out "a much clearer publicly-presented strategy" to tackle the pandemic.

Asked about the country's approach to the outbreak on BBC Radio 4's Today programme, he said: "I'm not sure we are quite getting it right."

Sir Paul continued: "Everybody involved, not just the politicians, the scientists and the doctors, we're all making mistakes and we have to try and learn from what mistakes have been made up until now.

"I get a sense the UK has been rather too much on the back foot, increasingly playing catch-up, firefighting through successive crises."

He suggested that what was needed was to "get a much clearer publicly-presented strategy as to what we're actually trying to do and the evidence upon which it is based".

Sir Paul added: "And we're not getting that in communications. Maybe there's a strategy there, I don't see it."

The expert suggested it was unclear who was making decisions in Government.

"I'm not completely convinced that we are actually being quite clear in having good leadership. The question I keep asking myself is: do we have a proper Government system in here that can combine tentative knowledge, scientific knowledge, with political action?

"And the question I'm constantly asking myself is: who is actually in charge of the decisions; who is developing the strategy and the operation and implementation of that strategy? Is it ministers? Is it Public Health England? The National Health Service? The Office for Life Sciences, SAGE? I don't know, but more importantly, do they know?"

Brandon Lewis, the Northern Ireland Secretary, took issue with Sir Paul’s criticisms, said he "wouldn't agree" with them, stressing how the Government had followed "the best advice that is out there".

He explained: “What we have seen through this is we as a Government have been very clear with people, very transparent with people. The Prime Minister himself has been very clear; the Prime Minister, ultimately, is responsible.”

Mr Lewis insisted ministers followed the “best advice that is out there” from scientific and medical advisers, ultimately it was ministers who made the decisions.

“One of the things we have seen throughout this process is our working to ensure we get as much information to people as we can to ensure that people understand what we can all do to play our part in keeping the R level down," he added.

Later today, the Government is expected to release new details about the current R rate, the virus infection rate, across the UK.