UK Prime Minister Boris Johnson is planning tougher new restrictions on social gatherings of more than six people in England starting next Monday, following a significant rise in the coronavirus cases.

A law change to be introduced will ban larger groups of friends and family meeting anywhere socially indoors or outdoors, to be enforced through a 100 pounds fine if people fail to comply and doubling on each offence up to a maximum of 3,200 pounds.

The rule will not apply to schools, workplaces or COVID-secure weddings, funerals and organised team sports, Downing Street said on Wednesday.

"We need to act now to stop the virus spreading. So we are simplifying and strengthening the rules on social contact making them easier to understand and for the police to enforce, said Johnson.

"It is absolutely critical that people now abide by these rules and remember the basics washing your hands, covering your face, keeping space from others, and getting a test if you have symptoms," he said.

Previously, guidance in England allowed gatherings of up to six people from different households outdoors or two households of any size, indoors or outdoors. But until now the police have had no powers to stop them unless gatherings exceeded 30 people.

Under the new law, any group of seven or more people gathering anywhere risks being dispersed by police or fined for non-compliance.

The change applies to people in England of all ages, and to gatherings indoors and outdoors, in private homes, public outdoor spaces, and venues such as pubs and restaurants.

The devolved administrations of Scotland, Wales and Northern Ireland set their own coronavirus restrictions but largely follow similar patterns as set out for England.

Downing Street said the UK PM held a virtual roundtable with police forces last week during which he was told that they wanted clearer rules and enforcement on social contact.

The stricter restrictions come in from next week as 8,396 new coronavirus cases were reported since Sunday, with a rise of 2,460 on Tuesday. Ministers and scientists have expressed concern over this spike in cases in the UK and urged the public to not relax social distancing and other safety measures.