The UK could be facing 50,000 new Covid-19 cases a day by mid-October, leading to 200 deaths a day a month later if the current rate of infection is not halted, the Government's chief scientific adviser Sir Patrick Vallance has warned.

Sir Patrick said the "vast majority of the population remain susceptible" to catching coronavirus and the current situation required swift action to bring the case numbers down.

In a televised press conference together with England's chief medical officer Professor Chris Whitty, Sir Patrick said there was "no doubt" the UK was in a situation where the numbers were increasing among all age groups.

He said: "At the moment, we think that the epidemic is doubling roughly every seven days."

“If, and that’s quite a big if, but if that continues unabated and this grows doubling every seven days… if that continued you would end up with something like 50,000 cases in the middle of October per day.

“50,000 cases per day would be expected to lead a month later, so the middle of November say, to 200-plus deaths per day.

“The challenge therefore is to make sure the doubling time does not stay at seven days.

“There are already things in place which are expected to slow that, and to make sure that we do not enter this exponential growth and end up with the problems that you would predict as a result of that.

“That requires speed, it requires action and it requires and it requires enough in order to be able to bring that down.”

He said “in every age group we’ve seen an increase”, adding this is not due to more testing, because of an increase in test positivity and results of the ONS study, which says around 70,000 people in the UK have Covid-19.

Prof Whitty said there was a need to "break unnecessary links" between households and there was a need to "change course".

He hinted at curbs to social lives being needed to prevent coronavirus spiralling out of control.

“You cannot in an epidemic just take your own risk, unfortunately you’re taking a risk on behalf of everybody else. It’s important that we see this as something we have to do collectively,” he said.

He said the four things to do are reducing individual risk by washing hands and using masks, quarantine measures, and investing in vaccines and drugs.

“The third one, and in many ways the most difficult, is that we have to break unnecessary links between households because that is the way in which this virus is transmitted,” he said.

“And this means reducing social contacts whether they are at work, and this is where we have enormous gratitude to all the businesses for example who have worked so hard to make their environments Covid-secure to reduce the risk, and also in social environments.

“We all know we cannot do this without some significant downsides.

“This is a balance of risk between if we don’t do enough the virus will take off – and at the moment that is the path we’re clearly on – and if we do not change course we are going to find ourselves in a very difficult problem.”