Dominic Raab has warned that a third wave of coronavirus is possible in the new year if social distancing measures are not followed.
The foreign secretary was asked on Sunday about the possibility of a third wave following a relaxation of lockdown rules over Christmas.
“There’s a risk of that if we don’t get the balance right,” he told BBC One's The Andrew Marr Show.
“But so far the R level is coming down – that's really important – and that's why we're starting with the tiered approach, more restrictive than some people would like.”
Asked whether there would be another national lockdown if people fail to comply with the rules, Raab said: “We're doing everything we can to avoid that.”
Raab said coronavirus cases would rise exponentially if restrictions were not applied on a wider level, such as across counties.
Earlier on Sunday he told Sky News: “Where you've got low levels in a particular area but it's surrounded by areas others with higher levels...
“If you don't apply on a wider levels – which is why we're using the countywide basis – the same restrictions, all that happens is the virus in those lower levels... goes up exponentially.”
But asked why that did not apply to Tier 2 London, the foreign secretary said: “You've got to look at the five principles.”
Raab also said that the new stricter tiered system announced by Boris Johnson this week is necessary to "bear down" on the pandemic.
"The reality is that we want to come out of national lockdown and stay out of it,” he added.
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"There is hope and there is light at the end of the tunnel at the prospect of regulatory approval of the vaccine being ready to be in place and distributed by the spring, which will allow a real step-change back to life resembling normal.
"The two things we need between now and then are this tiered approach so that we target the virus where it is the most dangerous.
"We are starting with a more restrictive approach than previously with the localised approach, but that allows us to ease up when we are confident the virus is going down and stabilised – there's a review every two weeks.
"The second thing is the testing and what we've seen, we've had 12 million people tested and we've seen in Liverpool with the community-wide testing... that really helps us to bear down on the virus.
"Those two things are the crucial bridge to that light at the end of the tunnel in the spring."
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