The last question comes from the Eastern Daily Press about child inequality.

Mr Johnson says: "One of the saddest things is it's kids from deprived backgrounds who really need to be back in school who perhaps aren't going back into the primary school classes that are open in the numbers that they could and should."

He urges parents to get their children back to school if they can and adds: "We're encouraging primary schools to take more pupils if they can fit them in."

Mr Johnson adds that there are areas of the country that do need more investment in their schools and school buildings and promises to do "more on that".

The next question is about whether people can now go on foreign holidays, if they stick to the rule of quarantining for 14 days.

Boris Johnson says the current advice is people should avoid non-essential travel, but the government will be reviewing the situation on 29 June.

He adds: "This is a fantastic country to go on holiday in and I wouldn't hesitate to recommend staycations."

Asked whether he has confidence in the NHS test and trace system, Chris Whitty says the "biggest thing" he is worried about is people not reporting they have symptoms or not isolating when asked.

"Isolating is a huge service to rest of society," he adds.

Image source, Getty Images

Four top US health officials testifying to congress today say they were never told by President Donald Trump to "slow down" testing. It comes after Trump told a rally in Oklahoma that he had asked his team to do less testing, in order to keep the official infection rate low.

Dr Anthony Fauci, the director of the National Institute of Allergy and Infectious Diseases, is one of the experts testifying.

Fauci described the US response as a "mixed bag" due to the nation's diversity.

He praised New York City's response, but said some states were now "seeing a disturbing surge of infection" and "increased community spread".

"A couple of days ago there were 30,000 new infections," in a single day, he said. "That’s very troubling to me."

"The next couple of weeks are going to be critical to address those surges that were seeing Texas, Florida Arizona, and other states."

The government advisers are asked about how long it could be before things truly get back to normal.

"I would be surprised and delighted if we weren't in this current situation through the winter and into next spring," says Prof Chris Whitty.

"I expect there to be a significant amount of coronavirus circulating at least into that time and I think it is going to be quite optimistic that for science to come fully to the rescue over that kind of timeframe.

"But I have an absolute confidence in the capacity of science to overcome infectious diseases - it has done that repeatedly and it will do that for this virus, whether that is by drugs, vaccines or indeed other things that may come into play.

"For medium to long term, I'm optimistic. But for the short to medium term, until this time next year, certainly I think we should be planning for this for what I consider to be the long haul into 2021."

Boris Johnson says "we've just got to adjust and make it work".

Mr Johnson is asked about why the changes only apply in England. Are the leaders of the devolved nations making a political point or scaremongering - or do they dispute the science?

Mr Johnson says "there's far more harmony" between the four nations than it may seem.

"I have no doubt the UK will continue to advance... at more or less the same pace."

The two advisers are asked whether they personally are happy with the changes.

Prof Chris Whitty says: "Personally am I comfortable with it - it's a balance of risk.

"I think this is a reasonable balance of risk. It's not risk free... nobody thinks it is."

He says they might at some point say one change went too far and was too much risk.

Prof Chris Whitty says it is "absolutely critical people stick to the guidance" and they can't just start acting as they did before the pandemic.

The next reporter asks whether the experts agree with the decision to ease lockdown in this way.

Sir Patrick Vallance says the reduction from 2m to 1m is "a perfectly reasonable approach to take, if mitigations are properly applied and people adhere to them".

He adds: "It is not risk free, it cannot be risk free."

But the chief scientific adviser adds: "The right way to deal with that is to monitor, measure and be prepared to take steps to reverse things if they need to be."

The next question is whether we can expect any further relaxation of social distancing before we have got a vaccine.

Boris Johnson says with the reduction in the R rate and incidents of the disease across the population it means "your chances of coming into physical proximity of somebody else who has the virus goes down", which will create "further opportunities to vary what our guidance is".

Chris Whitty says the "final decision" on any changes "are for elected ministers", repeating his warning that "we are going to be living with this virus for a very long time".

He also warns that "what goes down might go up" and winter could lead to "an increase in measures".

But, he concludes: "Everybody standing here understands this is going to be a long haul."

Chris Mason
Political Correspondent

By our calculation, this is the 92nd UK government news conference of this pandemic, and there have been two national addresses as well.

Until a few weeks ago, they happened seven days a week.

Then the weekend ones were ditched.

Now they are going as regular scheduled events, and will only happen when the government has something it sees as "significant" to tell us.

So no more "next slide please" from those behind the lecterns.

And no more of us reporters gurning into laptops on national telly and being told to unmute.

It will also mean a change in the TV schedules - which is good news for the gameshow Pointless, as presenter Richard Osman has tweeted about , externalthis afternoon.

Mr Johnson is asked by the BBC's Laura Kuenssberg whether he will take responsibility whatever happens next.

The PM says it is right that everybody is cautious with these new changes.

He adds: "Yes of course Laura I take a responsibility, the government takes a responsibility for these decisions."

Mr Johnson says "we are indebted" to the scientific advisers but "it is our responsibility" for the decisions.

To Chris Whitty, our correspondent asks whether he has changed his position on the 2m rule.

Prof Whitty says the advice to stay at 2m if you can remains - but the change is 1m plus where that isn't possible.

He adds: "People must take it incredibly seriously."

The second question from the public comes from Christine in Lincoln, asking what steps Public Health England are taking against contamination of meat after breakouts in abattoirs.

Sir Patrick Vallance says the Food Standards Agency has looked at the risk of meat passing on the virus, but said it was "very low".

However, he said the environment of an abattoir is an issue.

"There are several features of meat packing plants... it is cold and the virus prefers cold, it is often difficult to keep people separated, it is loud so people speak quite loudly and there are places where people huddle to have their coffee," he says.

Chris Whitty uses the example as a warning, saying in many environments the area of "maximum risk" is social and communal areas, so it is important for firms to consider those.

Boris Johnson takes his first question at today's No 10 briefing: When will primary care and dental practices be encouraged to work normally again?

Mr Johnson says: "With dental care we got back a few weeks ago in the NHS. And primary care should be functioning as normally as possible."

He urges people to see doctors and A&E if they have conditions that need attending to.

Prof Chris Whitty adds that GPs have been working throughout - although they have changed the way they work and many of those changes "make sense for the longer term".

He says there is a "steady movement" back to normal.

He adds that dental care is higher risk, but has started up again.

Moving on to the next expert, chief medical officer Chris Whitty says the government is taking these measures "because all of us in every country are having to find a sustainable balance to live alongside this virus".

He says "no decision is going to be risk free", but all of us have to play our part.

Prof Whitty says we all have to self-isolate if called and asked to, make sure we wash our hands and wear face coverings where we can't keep a distance.

He says when we meet other households, to stick to only one other household and follow social distancing rules.

It will be "safer, not completely safe" if the measures are taken at 1m, but he concludes: "It is absolutely critical every individual, every household and every firm takes these precautions seriously."

The UK government’s chief scientific adviser Sir Patrick Vallance says the latest reproduction rate – or R number, which is the average number of people each infected person passes the virus onto – is currently between 0.7 and 0.9 in the UK.

"The epidemic continues to shrink at the rate of something between 2 and 4% per day," he says.

He says it's important to remember the infection is "still here".

Mr Vallance adds that the estimated proportion of the population who have had the virus in England and have had antibodies is "something in the order of 5%", he says, adding that it shows a large proportion of the population are still susceptible to it.

The total number of deaths and the number of deaths involving Covid-19 has continued to decrease in the last week, he adds - and it is "coming back down towards normal".

But he adds a warning, saying: "Don't be fooled that this means it [the virus] has gone away.

"The disease is growing across the world, it's going down in the UK but it hasn't gone away."

He urged people to follow the guidelines, "to make sure Covid-secure really means Covid-secure by the way we all adhere to it".

Boris Johnson says, from 4 July, people will be able to meet with one other household.

This can take place inside your home, outdoors, or in a pub or restaurant, but social distancing must still take place.

But the PM urges people to "act responsibly".

He says: "We have only able to make these changes because we have persevered together and stuck to our path," adding that the British public has acted with "common sense and good humour".

But he warns "the fight is far from over" and Covid-19 is "a nasty virus that wants to take advantage to take advantage of our carelessness".

Johnson concludes: "I will not hesitate to put on the handbrake and reverse some of these changes at local or national level as required.

"But we can avoid that if we all continue to stay alert and do our bit to control the virus."

Boris Johnson lists a number of places that can re-open, such as hotels, bed and breakfasts, caravan parks, campsites, places of worship, bars, pubs and bingo halls.

"This has been an incredibly tough time for all these establishments, but I hope everyone in them can take confidence that they can open their doors again in a couple of weeks time," he says.

However, nightclubs, swimming pools and indoor gyms must remain closed because of the risk of transmission.

But the government is establishing task forces on how they too can open in a "Covid secure way".

Read more about what can reopen here.

The PM says the government "can now make life easier" for people to see more of their friends and family, get businesses back on their feet and get people back into jobs.

He confirms the 2m social distancing rule can now be modified, moving to "one metre plus".

He says with extra measures, such as installing screens, making sure people face away from each other and washing hands, this can be done safely.

On its final test - being confident that any adjustments to the current measures will not risk a second peak of infections that overwhelm the NHS – Mr Johnson says: "I can confirm the government judges we have met the fifth test".

He refers back to the government's roadmap in May, saying steps one and two were implemented as planned.

"Now, step three can be implemented as planned on 4 July," he adds.

Moving to PPE, Boris Johnson says the UK has made deals with 175 new suppliers to ensure supplies, with 2.2 billion items manufactured by home-grown companies.

He also says over eight million tests have been carried out, including over 822,000 antibody tests.

The PM adds the new NHS test and trace service has already advised 87,000 to self-isolate.

On ensuring the rate of infection has decreased to “manageable levels”, the PM says there is a difference of 4,048 from the rolling average mid-April to today – with 306,210 cases confirmed in total.

He says: "Sage believes infections across the UK are shrinking at a steady rate at between 2 and 4% every day."

Moving on to test two – seeing a sustained and consistent fall in the daily death rates – Boris Johnson says there has been a fall in daily deaths from 943 on 14 April to 121 today, when the seven-week rolling average is taken into account.

The PM says: "The second test is therefore still being met."