Boris Johnson has abandoned plans to avoid quarantine after being contacted by NHS Test and Trace following a furious political backlash.

The Prime Minister and Chancellor Rishi Sunak had originally planned to take daily tests rather than self-isolate following meetings last week with Health Secretary Sajid Javid who has tested positive for Covid-19.

But in a dramatic turnaround Downing Street said the two ministers would be self-isolating rather than taking part in a daily contact testing pilot.

“The Prime Minister has been contacted by NHS Test and Trace to say he is a contact of someone with Covid,” a spokesman said.

“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.”

The Prime Minister later tweeted a video of him saying that he had been pinged and asked to self-isolate after being in contact with Mr Javid.

“We did look briefly at the idea of us taking part in this scheme which allows people to test daily, but I think it is far more important that everyone sticks to the same rules, and that’s why I’m going to be self-isolating until Monday July 26,” he said

The U-turn came less that three hours after No 10 announced the two ministers would carry on working in Downing Street while taking daily tests.

It is part of a programme being trialled across 20 public and private sector organisations including Border Force and Network Rail as well as the Cabinet Office and No 10.

That sparked outrage amid warnings it risked undermining the Government’s messaging on continuing to self-isolation at a critical point in the pandemic.

Labour leader Sir Keir Starmer said the Government was in “chaos” at a time when in needed to maintain public confidence.

“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.

“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.”

Mr Sunak acknowledged that the sense that the rules were not being applied equally to everyone was damaging.

“Whilst the test and trace pilot is fairly restrictive, allowing only essential government business, I recognise that even the sense that the rules aren’t the same for everyone is wrong,” he tweeted.

“To that end I’ll be self-isolating as normal and not taking part in the pilot.”

The decision means the Prime Minister will now spend so-called “freedom day” on Monday when most lockdown restrictions end in England confined to his official country residence.

It came as one scientist involved in advising the Government warned that new cases could reach 200,000 a day before the current wave of the virus peaked.

Professor Neil Ferguson, whose modelling was instrumental in the Government’s decision to order the first lockdown in March 2020, said it was “inevitable” they would at least reach 100,000 a day.

“The real question is, do we get to double that or even higher? And that’s where the crystal ball starts to fail. We could get to 2,000 hospitalisations a day, 200,000 cases a day, but it’s much less certain,” he told BBC1’s The Andrew Marr Show.

He said that if cases continued to rise they could still place a “significant burden” on the health system.

“There you are talking about major disruption of services and cancellation of elective surgery and the backlog in the NHS getting longer and longer,” he said.

Communities Secretary Robert Jenrick said the current wave of the pandemic may not peak until September.

He acknowledged public “frustration” over the requirement to self-isolate when people came into contact with someone who has tested positive.

However he appealed to people to carry on using the NHS Covid app, despite the disruption to business and to public services, with tens of thousands off work after being “pinged”

He told Sky News’s Trevor Phillips On Sunday programme: “It is an important tool in our armoury to tackle the virus right now.

“Cases are still rising, hospitalisations are increasing and we won’t really expect this wave of the virus to peak until late August, maybe even early September.

“There are going to be some quite challenging weeks ahead.”