Video report by ITV News Political Correspondent Paul Brand
Lockdown measures will be made stricter in the North East of England, as coronavirus cases continue to rise sharply.
Health Secretary Matt Hancock said the existing measures were being tightened at the request of local councils because the virus was spreading.
It had been illegal for two households to mix inside or in a garden. But until now it was only guidance that they should not meet at public venues, including restaurants and pubs.
From Wednesday, it will be against the law for households to mix in any indoor setting.
The change in restrictions apply to Northumberland, Newcastle, North and South Tyneside, Gateshead, Sunderland and County Durham.
However, the leader of Newcastle Nick Forbes said in a statement on Twitter that the local authority was not informed of the changes.
Mr Forbes said: "While we have been in discussions with the government on potential further restrictions, the Secretary of State has once again stood up and announced changes without telling us he was about to do so.
"We want to work constructively with the government but the way these measures are being communicated in headlines and without detail does nothing for public confidence."
He added that the council has "demanded clarity" on "the new restrictions, testing and support for those businesses most affected".
The new rules will be enforced by law from 00:01 Wednesday 30 September, and those living in the North East will be subject to fines if the rules are broken.
Addressing MPs in the Commons, Mr Hancock said: "Today I must announce further measures for the parts of the North East where we introduced local action a fortnight ago.
"Unfortunately the number of cases continues to rise sharply. The incident rate across the area is now over 100 cases per 100,000."
Mr Hancock continued: "We know that a large number of these infections are taking place in indoor settings outside the home.
"And so at the request of the local councils, with whom we have been working closely, we will introduce legal restrictions on indoor mixing between households in any setting."
"We do not take these steps lightly but we must take them and take them now because we know that swift action is more likely to bring the virus under control and the quicker we can get this virus under control, the quicker we can restore the freedoms we all enjoy in the North East and across the country," he added.
The government said that, as of 9am on Monday, there had been a further 4,044 lab-confirmed cases of coronavirus in the UK, taking the overall number to 439,013.
A further 13 people had died within 28 days of testing positive for Covid-19 as of Monday.
The prime minister’s official spokesman said university students were subject to the same rules as the wider population in the areas where they live.
Boris Johnson has been urged to ensure online tuition at universities “becomes the norm”, amid concern over the impact of Covid-19 lockdowns on students.
Downing Street also said a 10pm curfew imposed last week struck the “right balance” between protecting the public and allowing pubs and restaurants to continue trading.
The curfew will remain in place despite chaotic scenes as pubs shut and warnings from some scientists advising the Government that it may be doing more harm than good.