Government sources have briefed that coronavirus rules will remain in place for another four weeks after the planned 21 June unlocking.

Senior ministers have decided delay lifting of all legal restrictions on social contact - meaning capacity limits for sports, pubs and cinemas will stay in place, and nightclubs will remain shut.

Prime Minister Boris Johnson is set to confirm the delay at a news conference later today.

Hertfordshire public health chief Jim McManus has also warned against the easing of Covid restrictions today, Monday June 21.

In his role as vice president of the Association of Directors of Public Health (ADPH) – Mr McManus has called for existing restrictions to be allowed continue.

Mr McManus warns that lifting all measures could lead to an increase in the number of cases and an increase in the number of people needing hospital admission.

He says it would risk the introduction of new variants to the UK, which could 'undermine' the vaccination programme and 'derail' the path back to normality.

He says: "Covid is not going to disappear on June 21 and lifting all measures as early as then risks reversing the significant progress we have made."

In making his case, Mr McManus says the determination and patience shown by communities during the pandemic has been "remarkable".

And he acknowledges that the impact on daily lives "cannot be understated".

But he says this is now a "crucial point" – and that it is vital to be guided by data and not dates.

He highlights the success of the vacination rollout, pointing to increasing evidence suggesting that the vaccination programme is breaking the link between Covid cases and deaths.

But he warns that as new variants take hold 'this break is becoming more uncetain'.

And he says the greater transmissability of the Delta variant has made the vaccine race 'even tighter'.

"For the foreseeable future, we will need to maintain some of the infection prevention and control measures which have now become habitual in the UK," he says.

"This includes hand hygiene, the use of face coverings and social distancing – 'hands, face, space'.

"An effective test, trace and isolate system – which includes adequate support and self-isolation payments – also remains critical to managing the spread of the virus in the longer term."

Mr McManus praises the work undertaken by businesses and organisations to ensure they have been able to operate as safely as possible.

He acknowkedgeds that people are feling 'optimistic', but he says he would like to see an extension of existing restrictions, rather than a complete lifting of measures.

"People are rightfully feeling optimistic about the coming months, and we have much to look forward to," he said.

"However, relaxing our vigilance now, even after we have had the vaccine, could undo what we have all made huge sacrifices to achieve.

"The alternatives of locking down or releasing all measures is a false one.

"Instead, we would like to see the extension of the current measures – brought into effect on May 17 – and a delay to the full reopening.

"This will help to prevent a further uptick in cases – particularly in areas experiencing high or enduring transmission – and allow time for more people to be vaccinated and protected against the Delta variant. Patience now, will pay off in the long run."

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