Vallance tells Boris to 'go hard and early' with masks and Plan B at first sign ...

Sir Patrick Vallance has called on Boris Johnson to go 'hard and early' with Covid restrictions at the first sign of infections rebounding in the UK.

England's chief scientific adviser today warned Britain was still in a 'very uncertain phase' of the pandemic, despite Covid cases falling for four days in a row.

He suggested that the Government's winter Plan B - which includes compulsory masks, working from home and vaccine passports - should not be taken off the table yet.

Downing Street is thought to have taken confidence from the fall in national infections in recent days and optimistic forecasts by SAGE.

Scientific advisers have told the Government that the epidemic could shrink naturally next month without curbs because of a combination of the booster vaccine rollout and growing natural immunity in children.

But warning against complacency today, Sir Patrick told the BBC Radio 4 Today programme: 'You need to absolutely be prepared (for plan B) and as soon as you start thinking "am I, or am I not going to do this? It looks close" is the time you need to push beyond your natural reluctance to do it and do it.

'This is obviously something the Government will have to consider carefully but we need to be ready to move fast if that occurs.'

Sir Patrick warned last month that the Prime Minister should go 'harder and faster' than appears to be necessary to contain the virus.

Medics and trade unions have called for Britain to switch to 'Plan B' immediately, which will see the reimposition of face masks and work from home guidance.

But ministers have so far held their nerve, insisting the NHS is not under 'unsustainable' pressure. Sources say there is a 'less than 20 per cent chance' that the plans will be activated.