The leader of Preston council says the city faces Government intervention after a dramatic rise in coronavirus cases.
The authority has now advised residents in the Lancashire city to avoid having visitors to their homes
However, there are no official restrictions such as the laws brought in for other parts of the county, as well as Greater Manchester and parts of West Yorkshire.
Speaking on BBC Breakfast, Preston City Council chief executive Adrian Phillips said: "We are not waiting for some Government announcement.
"We know our rates are increasing and they have increased over the last week to a level now where we are concerned that we could face Government intervention.
"We've been working with our communities to make sure we get those key messages out."
The council has also advised residents to wear face coverings at all times and to get tested even if they are experiencing only mild symptoms.
A statement on the authority's website said evidence from Public Health England showed a spike of coronavirus cases in Preston, with the majority of the spread through households and community.
It said: "The city is surrounded by areas that have had enforced measures implemented by Government and we want to act now to stop that from happening (in) Preston."
Mr Phillips told BBC Breakfast: "We are aware we have got community transmissions, we're aware they are across the city.
"There is a concentration in inner areas as there usually is in any urban environment, but it's in villages, it's in our suburbs.
"Covid has not gone away and it is us all taking that message on board and making sure that we don't relax our guard too much, that we maintain those key issues."
