British PM Johnson speaks to Trump after coronavirus diagnosis

The 55-year-old, who is believed to be the first world leader to have tested positive for the deadly virus, said his symptoms are mild which means he will carry on leading the response to the outbreak in the UK where the death toll jumped by 181 to hit 759 and the number of confirmed cases of COVID-19 stood at 14,543 on Friday.

Prime Minister Boris Johnson spoke with US President Donald Trump today. The President wished the Prime Minister a speedy recovery from coronavirus, a Downing Street spokesperson said on Friday evening.

They agreed to work together closely, along with the G7, the G20, and other international partners, to defeat the coronavirus pandemic, the spokesperson said.

The call came soon after Prime Minister Narendra Modi sent his best wishes to Johnson on Twitter, describing him as a fighter.

You're a fighter and you will overcome this challenge as well. Prayers for your good health and best wishes in ensuring a healthy UK, said Modi.

Earlier in the day, Johnson had posted an upbeat video message insisting that we will win against the virus if we carry on following the advice to "stay at home".

Be in no doubt that I can continue, thanks to the wizardry of modern technology, to communicate with all my top team to lead the national fightback against coronavirus, he said.

Carrie Symonds, Johnson's pregnant fiance, has reportedly moved out of Downing Street and is understood to be self-isolating separately with the couple's dog Dilyn at her south London flat.

It was also confirmed on Friday that Health Secretary Matt Hancock and the Chief Medical Officer, Professor Chris Whitty, both of whom have been leading the UK government fightback and were regulars at the daily Downing Street briefings through the crisis, have also tested positive with mild symptoms.

Working from home and wishing Boris Johnson and Matt Hancock a speedy recovery, said UK Chancellor Rishi Sunak in a Twitter post with an image of him at his desk.

The Indian-origin finance minister has also been seen working in close proximity with the UK prime minister and Hancock on the government's economic response to the crisis, most recently joining Johnson outside NO. 10 Downing Street in the clap for carers on Thursday night as his neighbour at No. 11.

Cabinet Office minister Michael Gove, the Chancellor of the Duchy of Lancaster, stepped in to host the daily Downing Street briefing on Friday evening instead, during which he said that the government was preparing to dramatically roll out thousands of antigen tests for frontline National Health Service (NHS) staff.

Increasing our testing capacity is absolutely crucial in our response to and our fight against coronavirus, said Gove.

This is a particular priority for those who work in the health and social care sector and are working so hard to keep us all safe, he said.

NHS and social care workers with symptoms or those who live with people who have symptoms will be checked starting with critical care doctors and nurses.

It follows criticism over a lack of testing for health workers. An antigen test determines if someone is currently infected and risks spreading it to others. A more effective antibody test, which confirms if someone has already had the virus and therefore immune, is still some way off with Public Health England saying that it is ordering it in the millions and will distribute it as soon as it is confident about its accuracy.

The British Medical Association (BMA) said the move towards testing NHS staff in England was "long overdue".

"For every healthy member of staff at home self-isolating needlessly when they do not have the virus, the NHS is short of someone who could be providing vital care to patients on the front line," said the BMA's Indian-origin chairman, Dr Chaand Nagpaul.

Previously, only seriously ill patients in hospital with flu-like symptoms were being routinely tested for the virus. At the moment about 6,000 people are tested daily. But by the end of March the government wants to test 10,000 people a day, rising to 25,000 by mid-April.

Expert analysis suggests the rate of infection in the UK has been doubling every three to four days and the number of cases are likely to continue to increase over the next two to three weeks, before the effects of social distancing lockdown measures and restrictions on everyday life begin to have an impact.