A SCIENTIFIC advisor to the UK Government has warned that Christmas will be "very difficult" in terms of curbing Covid.

Professor John Edmunds - a member of the government's Scientific Advisory Group for Emergencies (SAGE) - told ITV news that coronavirus cases were now "increasing exponentially".

It comes after the number of new infections across the UK reached 3000 on Monday, the highest since May.

Prof Edmunds, from the Faculty of Epidemiology and Population Health at the London School of Hygiene and Tropical Medicine, said autumn will be a challenge because the rate of reproduction of the virus - or R rate - is above one at a time when universities are due to re-open.

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In Scotland the most recent estimate put the R number as high as 1.4.

Prof Edmunds said there will be more local lockdowns, but that nationwide clampdowns may also have to be renewed as a result "an epidemiological effect" on the virus from schools and universities.

He said he thought some measures had been eased prematurely in England.

He said: "I didn't want us to relax measures so much that we couldn't open the schools safely without it tipping the reproduction number significantly above 1. And we are already above 1 and we've opened schools. So this is a risky period".

He added: "The epidemic continues to increase and then we have Christmas. And that is very difficult. What is Christmas? Well it's meeting with your family very close. Restaurants and pubs and stuff like that. And it's all high risk. And it's all indoors. Indoors makes a difference."

It comes as Nicola Sturgeon warned that it was a "dangerous delusion" to believe that current restrictions are excessive when most of the new cases are in young people.

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Bans on household visits are now in place in Glasgow, Renfrewshire, East Renfrewshire, West Dunbartonshire and East Dunbartonshire.

She stressed that every part of mainland Scotland had recorded cases in the past 24 hours, with three Covid deaths also recorded - the most in a single day since June.

The number of people in hospital with Covid in Scotland has also risen by 23 in the past 48 hours.

"That strikes me as something we should take note of," said the First Minister.

"This is a situation where Greater Glasgow and Clyde has a particularly severe challenge right now, but it's not the case that it is the only part of the country with a rise in cases.

"That rise in cases now is country-wide more or less, and although it's been driven by infection rates in younger people if we don't keep it under control we will start to see cases increase in all age groups, or older age groups, as well.

"I am genuinely of the view that this is a moment where if we don't take real notice of this and act accordingly, we are in a situation that is deteriorating and will deteriorate."