Boris Johnson and Rishi Sunak will self-isolate after Number 10 initially said they would not

How did Number 10's position change in just three hours? ITV News Politics Correspondent Romilly Weeks has the details

Boris Johnson has insisted "everyone sticks to the same rules" as he and Rishi Sunak begin fully self-isolating after being 'pinged' by the NHS app.

His words come just hours after Number 10 said both Prime Minister and Chancellor were part of a scheme that meant they were partially exempt.

Both politicians were contacted by Test and Trace after being in close contact with someone who has tested positive for Covid-19. Mr Johnson has confirmed his contact was Sajid Javid, who announced he had tested positive on Saturday.

On Sunday morning, Downing Street said the pair were involved in a daily contact testing pilot which would allow them to continue going into work while taking daily tests.

Amid a furious backlash, however, within three hours Number 10 made a U-turn and said both the Prime Minister and the Chancellor would now be fully self-isolating.

Labour has slammed the actions of the government, saying it is in "absolute chaos".

Downing Street initially said eligibility to be involved in the pilot is decided on a case by case basis. When not in work, both Mr Johnson and Mr Sunak would have needed to self-isolate.

In the first statement, Number 10 said it meant both politicians would be able to "continue to work from Downing Street."Just three hours later, a second statement was released announcing the U-turn.

"The Prime Minister has been contacted by NHS Test and Trace to say he is a contact of someone with Covid.

"He was at Chequers when contacted by Test and Trace and will remain there to isolate. He will not be taking part in the testing pilot.

"He will continue to conduct meetings with ministers remotely. The Chancellor has also been contacted and will also isolate as required and will not be taking part in the pilot."

Boris Johnson said in a video posted on social media: "We did look briefly at the idea of us taking part in the pilot scheme which allows people to test daily, but I think it’s far more important that everyone sticks to the same rules.

"That’s why I’m going to be self-isolating."

Mr Sunak tweeted to say: "I recognise that even the sense that the rules aren’t the same for everyone is wrong."

Labour described the three hour turnaround as "absolute chaos," with shadow health secretary Jonathan Ashworth calling on the government to come to the Commons to explain Number 10's initial response.

"There would have been parents this morning who've had to cope with their children isolating, or employers who've had to struggle because they've had staff isolating, absolutely outraged that Boris Johnson and Rishi Sunak were trying to exempt themselves from the rule.

"They've only U-turned because they've been caught out by this," he added.

ITV News Politics Correspondent Romilly Weeks attempts to answer the question: "What were the PM and Chancellor thinking?"

The opposition raised doubts about the legitimacy of the trial given that it was purportedly randomised.

"Three senior members of the Cabinet are all on this trial - even though it's supposed to be a random trial. There's something fishy going on here isn't there."

Labour leader Sir Keir Starmer said in a statement: "Boris Johnson and Rishi Sunak have been busted yet again for thinking the rules that we are all following don’t apply to them," he said in a statement.

"The public have done so much to stick to the rules. At a time when we need to maintain confidence in self isolation, parents, workers and businesses will be wondering what on earth is going on in Downing Street.

"The way the Prime Minister conducts himself creates chaos, makes for bad government and has deadly consequences for the British public. 

"Yet again the Conservatives fixed the rules to benefit themselves, and only backtracked when they were found out. They robbed the bank, got caught and have now offered to give the money back."

Before the about turn, Housing Secretary Robert Jenrick had defended the government, telling ITV News the pilot was "well known and longstanding".

Mr Jenrick said "a range of public sector organisations" were involved - including Border Force, TfL and Downing Street.

'This is a well known and longstanding pilot' says Robert Jenrick - before the U-turn

But the government was accused of "one rule for them and another for the rest of us," with hundreds of thousands of people across the country following the normal rules of self-isolation.

"We do urge people to continue to take action when they're approached by NHS Track and Trace," Mr Jenrick told ITV News as he defended the initial announcement.

"It's a really important part of our arsenal to tackle the virus [...] It is important and those people, including myself, should take action and follow the guidelines if you're approached by NHS Track and Trace."

Across the country businesses are warning of staff shortages due to their own staff being "pinged" by the app.

Up to a fifth of workers in companies are having to self-isolate after receiving a notification. More than half a million people received a notification in the week to July 7.

On Saturday, the London Underground became the latest to succumb with the Metropolitan line forced to close due to a shortage of control room staff.

It's unclear why this was the case given TfL's involvement in the scheme - TfL has been approached for comment.

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The timing could hardly have been worse for government with scientists voicing increasing concern at England's so-called "freedom day" - when Covid rules are eased - as cases continue to surge.

The Liberal Democrats said that Mr Javid’s positive test underlined the case for government to rethink its plans.

Health spokeswoman Munira Wilson said: “This shows no-one is safe from this deadly virus. By easing all restrictions with cases surging, they are experimenting with people’s lives.

“Right now, they are pursuing a strategy of survival of the fittest, where the young and clinically vulnerable will be left defenceless.”

Mr Johnson has repeatedly said he wants the lifting of lockdown to be “irreversible”, but in recent days ministers have begun to sound more cautious.

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