The Home Secretary has said police checking supermarket trolleys is "not appropriate" after a chief constable threatened to implement the measure to police the coronavirus regulations.
Northamptonshire Police Chief Constable Nick Adderley has since backtracked on his comments, describing his language as "clumsy".
Mr Adderley had said his force would consider roadblocks, marshalling supermarkets, and searching through shopping baskets and trolleys if people continued to flout the rules, saying their "three-week grace period" of educating and informing people had now ended.
Speaking at a press conference on Thursday, he said: "If things don't improve, and we don't get the compliance we would expect, then the next stage will be road blocks and it will be stopping people to ask why they are going, where they're going.
"This is about reasonableness and if people are not reasonable in terms of the journeys and the trips they are taking, they are going to fall foul of the law.
"We will not, at this stage, be setting up road blocks. We will not, at this stage, start to marshal supermarkets and checking the items in baskets and trolleys to see whether it's a legitimate, necessary item.
"But again, be under no illusion, if people do not heed the warnings and the pleas I'm making today, we will start to do that."
The comments were described as "outrageous" by civil liberties group Big Brother Watch, which compared the measures with a "police state".
Home Secretary Priti Patel said that approach "is not the guidance".
Speaking to Talk Radio, she said: "That's not appropriate, let me be clear about that.
"That is not the guidance, that is not down to the measures we've been adopting thus far.
"I think though, what we should just say about this weekend, in particular, is the weather is going to be good, it's Easter, we really do need to all take responsibility here, and it's not about overreach."
Ms Patel insisted she was "absolutely not" considering tougher coronavirus lockdown conditions.
She added: "I'll be very candid. Not everybody's going to get this right and it has taken a couple of weeks for these measures to bed in because this has been unprecedented, don't forget.
"The police have got these new powers that they are working with right now. We want our public places to be respected and utilised in the right way. We want people to make the most of at least getting out in the right kind of way, practising social distancing.
"But this is not about heavy-handed law enforcement. I think I really must emphasise that. There's a balance to this.
"I do pay credit to the police because these are extraordinary times. They exercise their judgment.
"Policing by consent means that officers, based on the guidance, exercise their judgment on the scenarios and the situations and the circumstances they are in.
"But the fact of the matter is, if you are having a garden party or a house party, or you're involved in a mass gathering in a public place, don't be surprised if the police do come up to you and ask you to stop doing that."
Seeking to clarify his earlier remarks, Mr Adderley used a Facebook Q&A to address the issue by saying: "There has been a really short grab clip of one of the statements I have actually made which has caused a bit of consternation, certainly on social media.
"This is the bit around, are we going to start marshalling supermarkets and checking shopping trolleys and baskets and so on."
Mr Adderley said he "may have been clumsy in that language" as he went on to read extracts of a briefing he had sent to his force – including instructions "not to carry out basket or trolley searches attempting to ascertain the relevance of the items purchased".
Silkie Carlo, director of Big Brother Watch, said: "The suggestion of police rummaging through people's shopping trolleys is outrageous.
"It would be completely disproportionate for police to start investigating shopping baskets or stopping every car at road checks, and there's no legal basis for them to do so.
"You'd think police have far more important work to do."
The news comes after Cheshire Police previously said in a tweet it had issued summonses after "multiple people from the same household going to the shops for non-essential items" but later admitted this part of the social media post was an "error".
Last month there were claims some convenience stores had been wrongly told to stop selling Easter eggs and hot cross buns by council officers as they were considered non-essential goods.
Police have powers to break up gatherings and fine people breaching lockdown rules, with legislation barring people from leaving their home unless they have a "reasonable excuse", which includes getting "basic necessities" such as food and medical supplies.
But the law does not prohibit buying certain types of food and drink and permits supermarkets, corner shops, off-licences, hardware stores, pet shops and post offices to stay open.
National Police Chiefs Council and the College of Policing guidance says there is no power to "stop and account" – where an officer stops someone and asks where they are going – and says road checks on every vehicle are "disproportionate".