The prime minister has said the government is in negotiation to secure anti-body tests capable of telling people whether they have picked up coronavirus - and that it would be prepared to buy “hundreds of thousands” of them.

In his daily briefing on the Covid-19 outbreak, Boris Johnson said the government was seeking to get hold of anti-body tests which he described as being similar in principle to pregnancy tests.

He said: “The scientific progress we are making will really start coming into play. We are rapidly becoming so much better at understanding the genomics at the heart of this virus and the medicines that may treat and cure it.

“Above all, we are getting better at testing. To give you an idea of what is coming down the track we are in negotiation today to buy a so-called ‘anti-body test’ as simple as a pregnancy test that can tell whether you have had the disease.

“It is early days, but if it works as its proponents claim we will literally buy hundreds of thousands of these kits as soon as practicable because obviously it has the potential to be a total game-changer.

“Once you know you have had it you will know you are likely to be less vulnerable, less likely to pass it on, and you can go back to work.”

Mr Johnson added that the government was aiming to increase daily tests from 10,000 per day, to 25,000 - eventually up to 250,000 per days.

He added; “That knowledge of where the virus will make a huge difference to our management of the disease and our ability to reduce disruption and economic difficulties.”

Meanwhile, asked about rising redundancies as a result of the outbreak, Mr Johnson said: “It’s very, very important everybody understands that we will stick by businesses and I hope that businesses will stick by their employees.

“This country is going to bounce back, we’re going to need some fantastic companies remaining to bounce back as well and it’s absolutely vital that everybody understands that now.”

He added: “On mass buying and the price issue, I really hope that retailers will continue to be reasonable. I certainly wouldn’t want to see profiteering of any kind.”