In comments to reporters on Friday evening, the prime minister said he did not want a second national lockdown but ministers were keeping “everything under review”.
“Obviously, we’re looking very carefully at the spread of the pandemic as it evolves over the last few days and there’s no question, as I’ve said for several weeks now, that we could expect [and] are now seeing a second wave coming in,” Mr Johnson said.
He added that a second lockdown was the “last thing anybody wants” but refused to rule out further restrictions if current social distancing measures, such as the so-called "rule of six”, do not slow the spread of the virus.
“I don’t want to go into bigger lockdown measures at all, we want to keep schools open and it is fantastic the schools have gone back in the way they have,” Mr Johnson said.
“We want to keep the economy open as far as we possibly can, we want to keep businesses going.
“The only way we can do that is obviously if people follow the guidance.”
The prime minister’s comments came after reports suggested the government was considering a two-week lockdown in October to stem the recent spike in new infections.
On Friday, the UK recorded 4,322 new confirmed cases of coronavirus, the highest since 1 May, and a further 27 deaths of people who had tested positive for Covid-19 in the past 28 days.
When asked whether ministers were considering a short “firebreak” lockdown, Mr Johnson said: “We’re watching it the whole time and as soon as we’ve got more to say, we’ll be saying it.”
He added: “If and when we have to go forward with other local or national measures or whatever, we will of course be explaining very clearly to everybody how we see it.”
The prime minister also reiterated that people should keep up with wearing a face covering, where necessary, and washing their hands regularly.
Additional reporting by PA