Around one in six people in London and one in 20 elsewhere in England have already had coronavirus, Matt Hancock said as he announced plans for antibody certificates.

Data gathered from an antibody surveillance study suggests 17% of people in London and around 5% in England have tested positive for antibodies to coronavirus, the Health Secretary told the daily Downing Street briefing.

It comes as the Government agreed a deal with pharmaceutical firms Roche and Abbott for more than 10 million antibody tests, to see if people have had Covid-19.

They will first be offered to health and social care staff as well as patients and care home residents, and the UK Government is also arranging supplies for the devolved administrations, with each nation deciding how to use its test allocation.

While it remains unclear what level of immunity people develop once they have had Covid-19, some experts hope a degree of immunity lasts for at least a year or two.

However, having antibodies does not automatically mean a person will not pass the virus onto somebody else.

Mr Hancock said: “This is an important milestone and it represents further progress in our national testing programme. Knowing you have these antibodies will help us to understand in the future if you are at lower risk of catching coronavirus, dying from coronavirus and of transmitting coronavirus.”

He also announced a trial of a rapid 20-minute test to tell people if they currently have Covid-19 following criticisms that people have been waiting days or weeks for test results.

A&E departments, GP testing hubs and care homes in Hampshire will all trial the new test, which will be used on up to 4,000 people.

The test does not need to be sent off to a lab and will be rolled out if it is shown to be effective, Mr Hancock said.

Before the press briefing, Downing Street announced a U-turn on the NHS surcharge, saying overseas health and care staff will be exempted from the fee levied on migrants to pay for the NHS.

It came after mounting pressure on Prime Minister Boris Johnson from senior Tories, with former party chairman Lord Patten calling the charge “appalling” and “monstrous”.

Labour leader Sir Keir Starmer, who urged the PM in the Commons on Wednesday to scrap the charge, said: “Boris Johnson is right to have U-turned and backed our proposal to remove the NHS charge for health professionals and care workers.

“This is a victory for common decency and the right thing to do. We cannot clap our carers one day and then charge them to use our NHS the next.”

The decision came a day after another U-turn when the Government extended a scheme offering indefinite leave to remain to the families of all NHS staff who die as a result of contracting coronavirus.

Meanwhile:

– The nation took to the doorstep for the ninth week in a row to clap for NHS carers and key workers who have put their lives at risk fighting Covid-19.

– John Holland-Kaye, chief executive of Heathrow Airport, signalled his tacit support for Government plans to impose a 14-day quarantine programme for anyone arriving in the UK from abroad, but firmly backed the idea of “air bridges” between countries with lower infection levels.

– EasyJet is to resume a small number of mainly domestic flights from 22 European airports from June 15.

– Crime in England and Wales has fallen by a quarter during the Covid-19 lockdown, new figures show.

– There was no evidence of increased infection from coronavirus among frontline NHS and care staff compared with those not working in such roles during two weeks in May, according to the ONS.

At the daily press briefing, Mr Hancock said certificates are being looked at for people who test positive for coronavirus antibodies.

He said: “It’s not just about the clinical advances that these tests can bring.

“It’s that knowing that you have these antibodies will help us to understand more in the future if you are at lower risk of catching coronavirus, of dying from coronavirus and of transmitting coronavirus.

“We’re developing this critical science to know the impact of a positive antibody test and to develop the systems of certification to ensure people who have positive antibodies can be given assurances of what they can safely do.”

Meanwhile, England’s chief medical officer Professor Chris Whitty told the briefing the total number of deaths from all causes was now down to the rate in an average winter.

He said “All cause mortality has come down at the same time as the Covid deaths have come down and it is now at roughly the rate it is at in an average winter.

“So, we are essentially having a winter in health terms, in terms of mortality, but in late spring and early summer.”

Prof Whitty also said care home deaths have peaked and have now come down.

On test, track and trace, Mr Hancock sought to play down the importance of the delayed app in the contact tracing process.

He had originally said the app would be rolled out by mid-May but it has now been delayed by several weeks.

The Government is aiming for 25,000 human contact tracers to be in place for June 1 – the earliest date for opening schools and non-essential shops in England.

Mr Hancock said: “The technology is an important part, but it is not the only part.”

He said trials of the app in the Isle of Wight had shown the human contact tracing elements were also important so people can understand the consequences of what is required if they have been near someone with coronavirus.

Professor John Newton, of Public Health England, said there could be advantages in doing the contact tracing process without the app initially.