LONDON (BLOOMBERG) - Britain is facing a leadership crisis as it heads into the peak of the coronavirus pandemic, with Prime Minister Boris Johnson fighting for his health in intensive care and his government under pressure to get a grip on the outbreak.

The 55-year-old Prime Minister was taken to the hospital on Sunday (April 5) night for routine tests after struggling to shake off Covid-19, but his condition worsened on Monday afternoon.

The pound fell after the government announced he had been moved to the facility for the most seriously ill patients.

Mr Johnson was receiving oxygen treatment at St Thomas' Hospital in London to help his breathing, but was conscious and not on a ventilator, officials said.

Foreign Secretary Dominic Raab is now deputising for Mr Johnson.

"There's an incredibly strong team spirit behind the Prime Minister - and making sure that we get all of the plans the Prime Minister's instructed us to deliver, to get them implemented as soon as possible," Mr Raab said in a pooled television interview.

Mr Johnson's deteriorating health intensifies the difficulties facing the country as it prepares for cases to climb over the next 10 days.

More than 5,000 people have died in Britain from the virus, and the nation remains in lockdown while the health service attempts to fill shortages of workers and vital medical kits, such as ventilators and protective masks.

TRUMP SUPPORT

It's an extraordinary turn of events for Mr Johnson. Just over two months ago, he was at the peak of his powers, celebrating Britain's departure from the European Union after scoring an emphatic election victory.

United States President Donald Trump, a supporter of Mr Johnson, said at a press briefing that he'd told pharmaceutical companies to get in touch with London to offer help.

Mr Trump cited "rather complex" therapeutic treatments for the virus with "really incredible results", but didn't specify them.

"When you get brought into intensive care, that gets very, very serious with this particular disease," Mr Trump said.

With Mr Johnson out of action, the untested Mr Raab will now need to get a grip on the government machine and coordinate the pandemic response.

Britain's strategy for defeating coronavirus has already come under strain, with ministers accepting they had not done enough to test people for infections.

Mr Johnson himself was criticised by medical experts and members of his own Conservative Party for failing to act quickly enough to close schools and ban public gatherings.

CABINET DIVISIONS

There have been divisions among Mr Johnson's officials during his period of isolation already, a situation that risks getting worse with Mr Raab, who was a leadership rival to Mr Johnson last year, now in charge.

Mr Johnson revealed on March 27 that he had tested positive for coronavirus and was going into isolation in his Downing Street apartment. His meals and official papers were left outside his door, but he continued to chair daily crisis meetings via video link.

The Premier recorded several "selfie" video messages for social media in recent days in which he insisted he was doing well and remained in charge. At times, though, he appeared short of breath and visibly unwell.

Throughout the day on Monday, Mr Johnson's officials said the Prime Minister remained in control of the government and was continuing to keep in touch with his team. He was "in good spirits" on Monday morning after a "comfortable" night, despite a cough and a fever, officials said.

Yet Mr Johnson's team gave few details when asked what had changed. Reporters raised questions over how seriously ill Mr Johnson was after Mr Raab disclosed that the pair had not spoken since last Saturday.

The Premier received good wishes from colleagues including his predecessors Theresa May and David Cameron, as well as his chief opponent, Labour Party leader Keir Starmer.

International leaders including Irish Premier Leo Varadkar and French President Emmanuel Macron also sent messages of support.

Mr Johnson's fiancee, Ms Carrie Symonds, who is pregnant, also had symptoms of the virus and had been isolating.