The Prime Minister has contradicted Home Secretary Priti Patel by saying members of the public should not report their neighbours for breaching the "rule of six" unless they are having large parties.
Any social gathering of more than six people in England is against the law, with people facing fines of up to £3,200 if they do not abide by the new measure, which applies to both indoor and outdoor settings.
On Tuesday, Ms Patel said she would report breaches she saw, later suggesting that families stopping to talk in the street could be breaking the new laws.
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Vanessa Feltz (left) sips tea with newly elected Witham MP Priti Patel during an event supporting Breast Cancer Care's Strawberry Tea fundraising campaign at the Houses of Parliament, Westminster, London.
Prime Minister David Cameron speaks with Witham MP Priti Patel in front of the Shah Sayyid Tomb in the Lodi Gardens in Delhi, India.
Prime Minister David Cameron and Witham MP Priti Patel, walk through Kolkata, India, where they visited the Howrah Bridge which was built by the Cleveland Bridge and Engineering Company.
Priti Patel who is the new Employment Minister, arrives at 10 Downing Street in London, as the PM puts the finishing touches to his new cabinet.
(left to right) Justice Secretary Michael Gove, Minister for Employment Priti Patel and Works and Pensions Secretary Iain Duncan Smith arrive in Downing Street to take part in the first Cabinet meeting since the Conservative Party won the General Election.
Indian Prime Minister Narendra Modi (centre) is flanked by Minister of State for the Foreign and Commonwealth Office, Hugo Swire (left) and Priti Patel (right) as he arrives at Heathrow Airport, London, for an official three day visit.
Employment minister Priti Patel launches a new government scheme to give extra careers advice to school pupils during a visit to Holy Trinity Catholic School in Birmingham.
(Left to right) John Whittingdale, Theresa Villiers, Michael Gove, Chris Grayling, Iain Duncan Smith and Priti Patel attend the launch of the Vote Leave campaign at the group's headquarters in central London.
EDITORIAL USE ONLY Minister for Employment Priti Patel tries her hand at painting with Matt Gray, Painting Skills Development Manager and Matt Pullen, CEO of AkzoNobel, as she officially opens AkzoNobel's Dulux Academy, the UK's first training facility dedicated to painters and decorators, Slough, Surrey.
Works and Pensions Secretary Stephen Crabb and Minister for Employment Priti Patel arrive for a Cabinet meeting in Downing Street, London.
Boris Johnson and Priti Patel meet workers at clothing and uniform manufacturers Simon Jersey in Accrington, Lancashire, during a visit as part of the Vote Leave EU referendum campaign.
Priti Patel speaks at a rally with Boris Johnson and Michael Gove (right) in Preston town centre, Lancashire, as part of the Vote Leave EU referendum campaign.
Michael Gove, Boris Johnson (centre) and Priti Patel pull pints of beer at the Old Chapel pub in Darwen in Lancashire, as part of the Vote Leave EU referendum campaign.
(left to right) Boris Johnson, Priti Patel and Michael Gove during a visit to Farmhouse Biscuits in Nelson, Lancashire, where they were campaigning on behalf of the Vote Leave EU referendum campaign.
Boris Johnson auctions a cow during a visit to a cattle auction in Clitheroe in Lancashire, where he along with Priti Patel and Michael Gove are campaigning on behalf of the Vote Leave EU referendum campaign.
Priti Patel MP visits Shree Sanatan Hindu Mandir Temple in Wembley, London, whilst out campaigning on behalf of the Vote Leave campaign.
Priti Patel arrives at White Waltham Airfield in Maidenhead, Berkshire, to meet veterans who will outline why they are voting to leave the EU.
(Left-right) Foreign Secretary Boris Johnson, International Development Secretary Priti Patel, Prime Minister Theresa May, Home Secretary Amber Rudd and Health Secretary Jeremy Hunt during Prime Minister's Questions in the House of Commons, London.
The Prince of Wales and the Duchess of Cornwall with International Development Secretary Priti Patel (right) during a reception and dinner for supporters of the British Asian Trust at Guildhall, London.
Priti Patel (left) with Boris Johnson's father Stanley Johnson and sister Rachel Johnson watch him speaking at a fringe event at the Conservative Party annual conference at the International Convention Centre, Birmingham. (Photo by Stefan Rousseau/PA Images via Getty Images)
Prime Minister Boris Johnson and Home Secretary Priti Patel on a walkabout with local police during a visit to North Road, Harbourne, Birmingham before announcing his plan to recruit an extra 20,000 police officers and an urgent review will take place of plans to make it easier for forces to use stop-and-search powers.
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Ms Patel told BBC Breakfast: "I think anybody would want to take responsibility and ensure we're not spreading this awful disease and therefore if I saw gatherings of more than six people clearly I would report that.
However, Boris Johnson has since urged people to speak with rulebreakers before notifying the authorities.
He told The Sun: "I have never much been in favour of sneak culture, myself.
"What people should do in the first instance obviously if they are concerned is raise it with their friends and neighbours.
"But I think what is reasonable for anyone to do is if they think there is a serious threat to public health as a result of their neighbours' activities – if there is some huge kind of Animal House party taking place, as I am sure, hot tubs and so forth, and there is a serious threat to public health then it's reasonable for the authorities to know."
Animal House is an American comedy which marked John Belushi's film debut as a hard-partying college fraternity member.
Mr Johnson's comments came after Policing Minister Kit Malthouse suggested that people should ring the non-emergency 101 number if they have concerns that their neighbours are breaching the laws.
As the rules came into effect on Monday, he said if people saw "that kind of thing" they should consider calling the police.
Chairman of the Police Federation of England and Wales John Apter previously said that police officers on the front line were "trying to interpret" the rules.
In response to a question about having "more guidance" on Good Morning Britain, he responded: "Maybe we should have 'guidance', because we haven't had any yet."
He said he understood the Government faced a "very fast-moving" situation, adding: "But my colleagues who are on the front line trying to interpret this law, trying to educate and work with the public, are now being accused of asking (people) to snitch on their neighbours."