BORIS Johnson is still showing signs of coronavirus, Downing Street has said, as it confirmed the Government is working with nine potential suppliers over a new Covid-19 antibody test.

The Prime Minister's seven days of self-isolation end tomorrow but it is unclear whether he plans to leave the Downing Street flat where he has been staying.

It comes as 2921 people were confirmed to have died in hospital after testing positive for coronavirus in the UK as of 5pm on Wednesday.

This is up by 569 from 2352 the day before and is the biggest day-on-day increase so far, just above the 563 reported the day before.

READ MORE: Coronavirus: Number of patients to die in Scotland rises by 50

The Prime Minister's official spokesman told a Westminster briefing: "The Prime Minister continues to have mild symptoms, but he does still have symptoms."

Asked if he would be leaving self-isolation tomorrow, the spokesman said: "We're following the guidelines from Public Health England (PHE) and from the chief medical officer which state that you need to self-isolate for a period of seven days, so no change in that."

Number 10 said work was ongoing with nine potential suppliers on developing an antibody test which would show whether people have had the virus.

Such a test would enable people to get back to work quickly and some experts say this type of testing is the quickest way out of the current lockdown.

The Prime Minister's spokesman said: "We are working as quickly as we can on that and as soon as a test is approved then we will announce it publicly."

He said the Government had previously been offered tests that had not met the required levels of accuracy "and therefore would not have been safe to use".

It was also suggested that immunity certificates to identify people who have had coronavirus are being considered by the Government.

The Prime Minister's spokesman said: "This is something which has been discussed in other countries.

"We have always said that we are watching closely what other countries are doing and we will always look to learn from ideas which could be helpful."

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