Police are mounting extra patrols to enforce new coronavirus restrictions over the weekend amid an increase in infections.
Senior officers urged the public to remember the pandemic remains a “real and deadly threat” during a spell of warm and sunny weather for much of the country.
“It is important to remember that we are still in the middle of a global pandemic, and the changes have been introduced to help control the spread of the virus, keep everybody safe and save lives,” a spokesperson said.
“Officers will patrol public spaces and will also respond to incidents where groups gather in numbers larger than six.”
National guidance given to officers says they should explain the law to people and encourage them to follow it voluntarily before handing out fines, which start at £100.
The amount is halved if payment is made within two weeks but doubles for further violations to a maximum of £3,200.
The law mainly applies to private gatherings and does not include pubs, restaurants or other businesses that have carried out risk assessments.
Greater Manchester Police said they stopped restrictions being breached after being called to reports of a wedding party at a home in Wythenshawe on Friday evening.
“Police attended and found that a gazebo had been erected in the garden,” the force tweeted.
“Officers prevented the illegal gathering before restrictions were breached.”
Assistant Chief Constable Claire Nix, of Kent Police, said there would be an increased presence in “key areas” around the county, as Covid-19 remains a “real and deadly threat”.
“The government has made it clear that the risk of increasing infections is too great to ignore and stricter social gathering rules have now come into effect to help keep everyone safe,” she added.
”There will be an increased presence in key locations around the county to ensure the current national advice is adhered to, such as preventing unlicensed music events and illegal gatherings.
“Covid-19 remains a real and deadly threat and we all need to take responsibility for our actions in helping reduce the spread of the virus and ultimately save lives.”
Police in Dorset, where large crowds have previously flocked to the beaches to enjoy the heat, also warned that anyone flouting the new “rule of six” over the weekend may be subject to fines.
Ollie Claydon, a spokesperson for the Met Office, said that the warm weekend temperatures would come ahead of a more “unsettled” week of weather.
“We're in for a dry and fine evening on Saturday, with clear conditions for central parts of the UK and northern Ireland,” he said.
“There's a risk of showers but temperatures will stay high.
”But then a cold front from the north west around lunchtime on Monday will herald the arrival of cooler, more unsettled weather next week.“