Thank you for following our coverage. We're wrapping up the live page for today but before we go, here's a round-up of Monday's main developments:

• UK PM Boris Johnson defended a new "stay alert" message on coronavirus, following criticism it was confusing
• US President Donald Trump says he told White House staff to wear masks after two administration members tested positive
• In Russia - the country with the third-highest number of infections - lockdown restrictions are to be eased from Tuesday
• The Chinese city of Wuhan, where the virus first emerged, reported new clusters of cases
• France began tentatively easing its lockdown after eight weeks of restrictions

Our coverage was brought to you by Jasmine Coleman-Taylor, Sean Fanning, Sophie Williams, Lauren Turner, Thom Poole, Hugo Bachega, Yaroslav Lukov, Doug Faulkner, Frank Keogh, Matt Henry, Justin Parkinson, Kate Whannel, Alex Bysouth, Saira Asher, Owen Amos, Andreas Illmer, and Tessa Wong.

Image source, Twitter

Twitter has said it started highlighting messages that contain "disputed or misleading information related to Covid-19".

The social media company said in a statement, external that "new labels and warning messages" would provide "additional context and information" to some of such tweets.

They would be used in cases where the risk of harm is not so great that the tweets would have to be removed.

But the company said it wouldn’t be directly fact-checking tweets or calling the highlighted ones false, stressing its users didn’t want it to decide what was true and what wasn’t.

Social media platforms have been under pressure to take action against coronavirus misinformation, ranging from conspiracy theories about its origins to advertisements for bogus treatments.

Image source, Getty Images

German Chancellor Angela Merkel has urged the public to stick to social distancing rules, after the infection rate grew following a relaxation in social distancing.

The national coronavirus reproduction number - or simply the R value - was higher than 1 for the third consecutive day, according to the Robert Koch Institute said.

The number was 1.07 on Monday, meaning that 100 infected people were on average transmitting the virus to 107 others.

The R rate must be held below 1 to prevent health services from being overwhelmed and continue the gradual easing of restrictions.

Germany is hailed by many experts as a success story in dealing with the outbreak.

The country currently has nearly 170,000 confirmed infections, with more than 7,400 coronavirus-related deaths.

Why R is the crucial number

Image source, AFP

As we reported earlier, Trump says the US has "prevailed" in coronavirus testing - while the banners behind him at the press conference read: "America leads the world in testing."

But is that true?

Perhaps the fairest way of comparing different countries' testing is to look at how many tests they're carrying out per 1,000 people.

This is because a country such as South Korea, whose population is smaller than a sixth of the US's, will need a lower overall testing capacity in order to control the virus.

According to official figures collated by science publication Our World in Data, the US has currently tested 26.31 out of every 1,000 people. While this is higher than countries such as France and the UK, other nations are testing far more people per 1,000 than the US is.

Portugal, which has been held up as an example of how early and widespread testing can help control the virus early, has tested 47.66 per 1,000 people. Israel, which recently increased its testing operation, has now tested 50.35 out of 1,000. Bahrain, meanwhile, has managed to test almost 10% of its population of just over 1.5m.

President's Trump news conference ended abruptly after he clashed with reporters.

He said during the briefing the US led the world on testing, but CBS White House correspondent Weijia Jiang asked him why it was a "global competition" for him when Americans were dying.

"Go ask China," Trump said to Jiang, who is Asian-American.

Jiang responded by asking Trump why he was personally telling her to speak to China, who replied he was saying it to anyone who would ask a "nasty question like that".

He then refused to take questions from a CNN reporter, who had let Jiang ask follow-up questions, before thanking everyone there and walking off.

Trump is asked if he was behind the White House memo today which requires anyone in the West Wing to wear a face mask.

“Yes I did, I required that” says President Trump, who has previously described himself as a germaphobe.

Trump reportedly was furious when he found out his personal valet, who serves him his meals, tested positive for the virus.

Trump was asked why he wants US businesses to reopen without testing easily available, while White House officials have testing on demand.

"If we didn't get the tests done you'd be up here complaining that we weren't getting the tests done," he said.

"You complain that we're getting too many tests," he added, "so we can't win."

Trump says the US is now conducting 300,000 tests per day and will hit the 10m mark for total tests this week.

According to the Covid Tracking Project, a non-profit charity, the US conducted an average of 248,000 daily tests in the first week of May.

However, prominent public health researchers at Harvard University say at least 900,000 daily tests are needed before the US should reopen.

As of this week, the US has tested only 2.75% of its 330m population, and no state has tested 10% of residents.

In over a dozen states where lockdown measures have been relaxed, including Texas, South Carolina and Arizona, less than two percent of residents have been tested.

Trump said in his opening address the US has "prevailed".

Asked to clarify, the president says he was talking about the nation's testing capability.

“You never prevail when you have the kind of death you are talking about," he said.

"We have done a great job on testing and it is a big, important function. We have prevailed, we have the best equipment anywhere in the world."

Image source, Reuters

Asked about the White House staff who tested positive for coronavirus Trump said "I don’t think the system broke down at all".

"One person tested positive, surprisingly, because the previous day they tested negative," he says.

"That's not breaking down. It's the hidden enemy. It's the hidden enemy, Let's remember that."

He adds that people have been going and coming from the White House only because they are essential workers.

"We're running a country," he said.

Image source, Reuters

US President Donald Trump says the country has increased the number of tests it conducts each day from 150,000 to 300,000.

The total number of tests performed in the US passed nine million on Monday and is expected to reach 10 million later this week.

The FDA has authorised 79 diagnostic tests on 25 different devices. It authorised the first antigen test on Friday and says 300,000 could be on the market within the next few weeks - such tests quickly detect whether a person has been infected by the coronavirus.

Trump says that the US economy will improve in the coming months, a phase that he calls "transitioning into greatness".

"Next year we're going to have one of the best years we've ever had. Because it's a pent-up demand," he says, calling it "a demand that we’ve never seen".

Like most economies, the US has been hard hit by the coronavirus pandemic - last week unemployment claims since mid-March hit 33 million.

Trump is speaking from the White House Rose Garden.

He begins by touting US coronavirus testing, which he says is part of the plan to "gradually and safely reopen America", adding that many are very enthusiastic to get back to work.

Trump's son-in-law and top aide Jared Kushner has been seen wearing a mask as he watched the president speak.

There have been more than four million cases of coronavirus recorded worldwide.

The charts below show how the worst-hit European countries appear to have passed through the peak.

However, Russia is alongside Brazil, Mexico and Peru as one of the countries where the death toll from the virus is rising fast.

Below, we see that the number of new cases and deaths from the virus in the US appears to have also moved beyond its peak.

The east coast - particularly New York state - is the hardest-hit area.

The White House has sent a memo to staff directing more aides to wear masks when in the West Wing or avoid President Trump's office altogether if possible.

The memo was obtained by US media moments before Trump is due to deliver remarks from the White House on the role of testing in the effort to reopen the country's economy.

It also comes as three high-ranking members of the White House coronavirus taskforce - including top disease expert Anthony Fauci - are in self-isolation after two White House staff members tested positive.

According to US media, the latest White House memo on masks is unlikely to apply to Trump, who has so far not worn one during the pandemic.

Our colleague Anthony Zurcher is at the White House, where he says the number of Trump aides wearing masks has already risen since last week.

He says all of the press aides are donning masks for Trump's briefing.

Reality Check

Image source, Getty Images

Prime Minister Boris Johnson said the government hit its daily testing target with 100,490 tests on Sunday.

The target, set by Health Secretary Matt Hancock last month, was for 100,000 tests per day in the UK to diagnose coronavirus.

The government said the figure was reached on 30 April and then 1 May - although there was some criticism about how tests were counted - but the target was then missed for eight consecutive days.

Johnson has talked of raising the target further to 200,000 tests per day by the end of this month.

We have been looking at how the government is getting on with seven of its coronavirus targets - including testing.

Nduka Orjinmo
BBC News, Lagos

The authorities in Nigeria's oil-rich southern Rivers state have demolished two hotels over an alleged breach of lockdown rules intended to contain the spread of coronavirus.

State Governor Nyesom Wike, who supervised the tearing down of Edemete Hotel and Prodest Home on Sunday, said the operators had flouted an order that hotels should be closed.

He said people who had tested positive for the virus had been found in hotels across the state. But he did not say if anyone who had Covid-19 had been staying in either of the demolished hotels.

Read the full story here.

Reality Check

Image source, Press Association

The UK prime minister was asked about the childcare provision for people expected to go back to work before schools reopen.

Boris Johnson says if people do not have access to childcare, it is only fair to see that as a barrier to their ability to go back to work.

People who cannot work from home - such as those in the manufacturing and construction sectors - are being "actively encouraged" to return to work from Wednesday.

But ministers say schools in England should prepare to begin to open for more pupils from 1 June, with only selected year groups - including Reception, Year 1 and Year 6 - going back in smaller class sizes.

Secondary schools and FE colleges are also being told to plan for some face-to-face contact with Year 10 and 12 pupils.

Read more about the timetable for schools reopening.

• Prime Minister Boris Johnson defended the UK government's decision to change the "stay at home" message for England, insisting that "stay alert" is "absolutely the right message for our country", saying the French government had gone with "roughly the same sort of thing"
• He sought to explain the message, criticised by many as confusing, saying "we're asking people to stay alert… for the vast majority that means staying at home as much as possible"
• According to Johnson, if people in England do not have access to childcare, "then I think it's only fair to regard that as an obvious barrier to their ability to go back to work and I'm sure employers would agree with that"

• Chief Medical Officer for England Prof Chris Whitty said scientists had decided the risk of transmission was "much lower outdoors" than indoors, but that the risk was "not zero"
• Chris Whitty said he was "very confident" a solution to coronavirus would be found, but that it would "take time"

The last question of the press conference concerned whether schools contribute to the infection rate.

"They do contribute a certain amount, and this is what is being modelled carefully," replied Chris Whitty.

"We are very committed to publishing all of the science behind Sage.

"That is happening but never as fast as people want."