Police in Scotland will be given powers to break up and disperse house parties, First Minister Nicola Sturgeon has announced.
The move comes amid concerns about links between large indoor gatherings and the spread of Covid-19 cases.
Ms Sturgeon said large house parties posed "a real and significant risk of causing clusters and outbreaks".
She said the new powers would be used as a "last resort" where there was a "flagrant" breach of the rules.
The new regulations are expected come into force on Friday 28 August.
Councils will also be given new powers to close down pubs and cafes that do not comply with Covid-19 regulations.
"We believe that both of these new powers are necessary to continue to suppress the virus," said Ms Sturgeon.
In recent days clusters of cases in Glasgow and Lanarkshire, involving a number of school pupils, have been linked to house parties.
The first minister told the Scottish Parliament that these gatherings posed a "very significant transmission risk".
"If the virus is present at an event like that there is very high likelihood that people at the event get the virus," she said.
"That is why we advise strict limits on indoor gatherings."
No more than eight people from a maximum of three different households should be meeting together indoors - either in homes, or in pubs and restaurants.
Ms Sturgeon said the government had considered carefully which further steps could be taken to minimise the risk of transmission at indoor gatherings.
A significant outbreak which led to the reintroduction of lockdown rules in Aberdeen two weeks ago was linked to bars and nightlife in the city.
Ms Sturgeon said not all hospitality businesses had implemented the guidance effectively.
"We intend to give local authorities the power to act in respect of individual, specific premises that are breaching guidelines and risking transmission of the virus," she said.
"This power would enable local authorities either to close such premises - or to impose conditions on their opening - where they deem that is necessary for the purpose of preventing, protecting against, or controlling the spread of infection."
Ms Sturgeon also announced on Thursday that gyms, swimming pools and indoor sports courts will be able to reopen from 31 August - two weeks earlier than previously indicated.