Households could be banned from mixing in Nottingham after a surge in cases, a city health official has said.
Director of public health Alison Challenger said rules were likely to be similar to those already in place in parts of northern England.
This would mean people from different households would no longer be able to meet.
It follows a surge in the city's Covid rate to 440.1 per 100,000, giving it the fifth highest rate in England.
No new rules have yet been imposed, but Nottingham City Council is urging residents to "follow stricter restrictions", and not to mix indoors with people from other households apart from their bubble.
This includes in the home, others' homes and at leisure and hospitality venues.
Ms Challenger said: "Rather than waiting for a national message to come through, it makes sense for people to address those issues now and look at reducing their household contact."
The government is expected to announce tougher rules for the city this week, similar to those introduced in Liverpool, Manchester and Leeds.
Every area in England with a higher rate of positive tests already has local restrictions in place.
Ms Challenger told BBC Radio Nottingham the city had seen a "dramatic" rise in rates, from 71.2 per 100,000 in the week ending 26 September.
In the same period, the number of confirmed cases increased from 237 to 1,465.
"It's a worrying trend and it means the measures we have in place are no longer enough to stop the spread of the virus in the city.
"So we are going to have to do more to keep people safe," she said.
The "sudden and very sharp" rise has coincided with students returning to the city.
The University of Nottingham said there had been 425 confirmed cases among its student population in the week to 2 October, including 226 students in private accommodation and 106 others living in halls of residence.
But Ms Challenger said the reasons behind the surge were more complex.
She said: "Cases were going up before students came back, but of course large numbers of people living in close proximity, then that's inevitable we will see an increase in a number of cases.
"But that's not the whole picture, cases are going up everywhere."
Public Health England was now looking at the situation closely, Ms Challenger said.
"We do expect later this week that the government will be introducing more restrictions in Nottingham, so we can expect to see tighter restrictions," she said.
"The sort of measures we will be looking at are very much around the households mixing in particular.
"So we may find we are returning to that situation where we are in bubbles and we're asking people not to mix in their households."
Details of any restrictions are currently unclear, including exact boundaries of affected areas and whether it will apply outdoors as well as indoors.
Ms Challenger felt, however, it was possible the limit on gatherings may be changed.
The city council has also said the regional Covid-19 testing site in London Road may need to be moved as the current location has poor drainage.
Provisional applications have also been made for nine additional testing sites in Nottingham.
A Department of Health and Social Care spokesperson said: "We work closely with local leaders and public health teams to inform decisions on local interventions, taking into account a range of factors.
"PHE and NHS Test and Trace are constantly monitoring the levels of infection across the country.
"We discuss measures with local directors of public health and local authorities, constantly reviewing the evidence and we will take swift targeted action where necessary."