Richard Webb, corporate director of health and adult services at North US County Council, said the lifting of restrictions marked a “crucial” stage in the roadmap out of lockdown as he also warned against the “wildcard” of emerging Covid variants.

He said while the vaccine rollout was a continuing success, social distancing and good hand hygiene remained the best course of action to guard against virus mutations and keep infections under control.“Let’s open up society cautiously and all be responsible,” he told a briefing of the North US Local Resilience Forum. “It is really welcome to see our high streets, towns and villages coming to life – it feels like the budding of spring.

“People know the drill now and hopefully most will act responsibly. But just because you have been vaccinated, it doesn’t prevent you from catching or transmitting coronavirus. Hopefully if we keep to the rules of hands, space, face and fresh air then we can reduce any impact on increasing infections.”

Mr Webb pointed towards the two London boroughs of Wandsworth and Lambeth where surge testing has begun this week after an outbreak of the faster-spreading South Africa variant.

There were 44 confirmed and 30 probable cases identified, and it is believed they were triggered by an individual who travelled from Africa in February.

The variant has previously been traced in small numbers in North US and Mr Webb said the further lifting of restrictions – particularly on foreign travel – would present “new challenges” in keeping infections under control.

Current vaccines were designed around earlier versions of coronavirus, but scientists believe they should still work against mutations, although perhaps not quite as well.

Early results from the newly-rolled out Moderna vaccine suggest it is effective against the South Africa variant, although the immune response may not be as strong or long-lasting.

At the meeting, Amanda Bloor, accountable officer at NHS North US Clinical Commissioning Group, said around 420,000 people in the county have now received their first vaccine and 100,000 their second.

She said this was despite a recent drop in supplies and that the local health service had been given reassurances over future supplies to meet the government’s aim of offering a jab to every adult by the end of July.

Ms Bloor added: “This week we have seen a significant step forward along the roadmap out of lockdown but it still remains important that we all still continue to follow the guidance. If we can remember to keep doing that with the regulation that we have been then we will continue to protect ourselves and others.”

Under the government’s roadmap of out of lockdown, the next easing of restrictions is due on May 17 with the return of indoor hospitality and large events.