This is the moment a police van was seen going around a park in south London advising people not to sunbathe, but only exercise.
It comes as Health Secretary Matt Hancock has said sunbathing in public spaces is against the coronavirus social distancing rules.
He added that if too many people flout the lockdown rules, the government will have to take action on allowing exercise.
Officers drove through Peckham Rye Park yesterday afternoon, blaring: "No sunbathing, exercise only, please. Thank you."
A clip filmed at the scene shows crowds of people at the park and, even though many seem to be playing sports, others seem to be sunbathing and enjoying the warm weather.
Britons have been asked to resist to the temptation of going out because of the sunny weather this weekend to help the fight against the outbreak of Covid-19.
Mr Hancock warned those flouting the advice that they were putting people's lives at risk.
He told Sky News's Sophy Ridge On Sunday: "The vast majority of people are following the public health advice, which is absolutely critical, and staying at home.
"But there are a small minority of people who are still not doing that - it's quite unbelievable frankly to see that there are some people who are not following the advice."
Asked whether sunbathing in public spaces was against the law, he said: "Sunbathing is against the rules that have been set out for important public health reasons."
He warned those who are flouting the guidance: "You are putting others' lives at risk and you are putting yourself in harm's way."
Matt Hancock has warned that the Government may restrict people's freedom to exercise outdoors if it is clear that people are flouting the rules.
Speaking to the BBC's Andrew Marr Show, he said: "We've said it's OK to go for exercise because both the physical and mental health benefits of getting some exercise are really important.
"I don't want to have to take away exercise as a reason to leave home... if too many people are not following the rules.
"At the moment the vast majority of people are (following the guidance) but people should not break the rules because that will mean that the virus spreads more and then we might have to take further action."
It comes after 41,903 people tested positive for coronavirus in the UK - with 4,313 deaths confirmed yesterday.
More than 3,000 people ignored the coronavirus lockdown rules on Saturday afternoon and flocked to Brockwell Park in south London.
Lambeth Council announced it would close the park today after advice to stay home was ignored.
The authority said in a statement: "Despite clear advice, over 3000 people spent today in Brockwell Park, many of them sunbathing or in large groups. This is unacceptable.
"Unfortunately, the actions of a minority now means that, following police advice, Brockwell Park will be closed tomorrow. #StayHome.
"We are sorry we've had to take this decision. This wouldn't need to happen if people followed the clear instructions from the Govt.
"We are doing this for the wider safety of the public. A minority of people have not followed the guidance - regrettably we have to act."
London Mayor Sadiq Khan has warned people not to gather in large groups amid social distancing rules - adding police would "step in" to stop those breaking the rules.
Queenstown Police tweeted: "It is upsetting to see so many groups of people ignoring the public health Covid-19 Laws.
"We have engaged with many people on the estates yesterday and #BatterseaPark today who have been sat out enjoying the sun with a drink. This isn't a holiday and needs to be taken seriously."
Police in the UK capital were also forced to break up an 18th birthday attended by 25 guests in east London yesterday.
Surrey Road Police also shared a shocking video of Richmond Bridge in West London packed with people out walking along the Thames.
In a tweet, they urged Brits to "PLEASE PLEASE PLEASE stay at home."
Boris Johnson said: "I just want to say one crucial thing, to everybody thinking about this weekend and what may be some fine weather.
"I reckon a lot of people will be starting to think that this is all going on for quite a long time and they'd rather be getting out.
"Everyone may be getting a bit stir crazy.
"There may be a temptation to get out there and hang out and start to break the regulations.
"I just urge you, not to do that.
"Please, please, stick with the guidance now."
Under strict lockdown measures, Brits are expected to stay indoors and only go outside for essential shopping, medical reasons, one form of exercise a day and to work from home if possible.
