Boris Johnson is back in Downing Street, having returned to take charge of the Government's response to the coronavirus outbreak.

The Prime Minister is resuming full-time duties at the head of the Government three weeks after he was admitted to hospital with the disease.

He will chair the regular morning meeting of the Government's Covid-19 "war cabinet" before heading into a series of meetings with senior ministers and officials.

Foreign Secretary Dominic Raab - who has been deputising for him in his absence - said he was "raring to go" after a fortnight convalescing at Chequers, his official country residence.

He arrived back on Sunday evening to a growing clamour from senior Tories to begin lifting the lockdown amid mounting concern at the damage it is causing to the economy.

Scientists advising the Government have warned any relaxation risks a renewed flare up just as the numbers of patients in hospital with the disease is beginning to fall.

Over the weekend, ministers highlighted a warning by Bank of England governor Andrew Bailey of the economic devastation a second wave of the disease would cause.

Mr Raab said the outbreak was at a "delicate and dangerous" phase and people would have to get used to a "new normal" - with social distancing measures set to remain in place for "some time" to come.

The PM first said he tested positive for Covid-19 on March 27, and was admitted to hospital on April 5 after his condition deteriorated.

He spent two nights in the intensive care unit at St Thomas’ Hospital before finally being released from hospital on April 12 and spent most of his recovery at his country seat of Chequers in Buckinghamshire.

Now he is back at Downing Street, here are the most challenging problems on his to-do list.

– Lockdown

There is no end in sight for lifting lockdown measures – and although the situation will be reviewed again on May 7, there is still no sign of an exit plan.

Labour leader Sir Keir Starmer has accused the Government of treating the public “like children” for refusing even to give a hint of what a future strategy could look like.

Coronavirus – Sat Apr 25, 2020Home Secretary Priti Patel during a media briefing (Pippa Fowles/10 Downing Street/Crown Copyright)

At the Downing Street briefing on Saturday, Home Secretary Priti Patel said it would be “irresponsible” to get people’s hopes up.

– Death toll

The Government has a lot of explaining to do now the deaths in hospital have exceeded 20,000, and experts fear we are on course to have one of the highest mortality rates in Europe.

This weekend’s rises shattered health officials’ best-case-scenario hopes of keeping this figure to 20,000 or below.

HEALTH Coronavirus(PA Graphics)

Once the full extent of deaths in care homes is known, this figure could jump up by many thousands.

– Sage 

The PM’s controversial chief adviser Dominic Cummings attracted yet more negative headlines after it emerged he had attended meetings the scientific group convened to advise the Government in times of emergency.

It has opened the Government up to allegations of letting politics taint the scientific advice issued by The Scientific Advisory Group for Emergencies (Sage), that experts say only greater transparency will solve.

CummingsDominic Cummings’ attendance at Sage meetings has caused controversy (Jonathan Brady/PA)

Dr Paul Hunter, professor of medicine at the university of East Anglia and adviser to the World Health Organisation, said: “(If Cummings) was contributing to the discussion, then that means we need to be very cautious about the conclusions of Sage.

“Because whether or not he did influence the outcomes we can’t know for certain, and therefore the validity of the advice coming out of the committee might be flawed.”

– PPE

The problem of adequate levels of PPE is a headache the Government has made little progress on in Mr Johnson’s absence.

According to a study published by the Royal Pharmaceutical Society on Wednesday, over a third of frontline workers surveyed said they were still unable to access continuous supplies of PPE.

HEALTH Coronavirus PPE(PA Graphics)

A promised shipment of 400,000 medical gowns due to arrive earlier this week turned out to be closer to 32,000, according to media reports.

And many UK business claiming to be able to adapt manufacturing to supply PPE complain they have been ignored by the Government when they approached offered their services.

– Testing

The Government previously set a target of 100,000 Covid-19 tests being conducted every day by the end of the month, but with just five days to go that ambition looks doomed.

Coronavirus – Sun Apr 26, 2020A pilot key worker testing centre at Poppleton Park & Ride site in York (Danny Lawson/PA)

The Home Secretary said on Saturday only 28,760 tests had been carried out on Friday, while a new online booking service has also facing some serious teething problems.

Home testing kits were listed as “unavailable” on the site just 15 minutes after it reopened on Saturday morning, will slots at regional drive through sites were also booked out in just two hours.

– Lockdown fatigue

Before he was taken to hospital, Mr Johnson was trying to ram home the “Stay home, protect the NHS, save lives” message, but discipline has been slipping.

Many police forces across the UK have complained of having to deal with flagrant breaches of the shutdown rules, while traffic data revealed car journeys had crept up by three percentage points this week.

And mobility data released by Apple revealed that in recent days searches for maps for walking or driving had increased by eight percentage points.