Divisions in the UK are set to be laid bare with people returning from Portugal to Scotland facing a 14-day quarantine but not those returning to England and Northern Ireland.

The UK and Scottish governments entered a tit-for-tat on Friday as they differed once again on how to deal with rising Covid-19 levels in Europe.

New rules have dictated that from 4am on Saturday people arriving in Scotland from Portugal must self-isolate for a fortnight.

The latest Joint Biosecurity Centre data...indicated a significant rise in the prevalence of the virus in Portugal

Portugal had only been removed from the UK quarantine list two weeks ago but there had been suggestions the Department for Transport would opt to reinstate it after the country’s coronavirus cases rose to more than 20 cases per 100,000 people – the threshold used for past travel decisions.

Fresh restrictions have already been reintroduced for the popular tourist destination by the Welsh government but England and Northern Ireland opted not to collapse the so-called travel corridor with Portugal.

Scotland on Thursday reintroduced quarantine for those returning from Greece and while Wales did the same for six Greek islands, including Crete and Zante, England and Northern Ireland resisted.

Despite the differences, Prime Minister Boris Johnson insisted that “overwhelmingly the UK is proceeding as one”.

But earlier in the day, Transport Secretary Grant Shapps said there was now “confusion” over differing quarantine rules across the union and accused Scotland of having “jumped the gun” on imposing restrictions on Greece.

A spokesman for the Scottish Government hit back, saying there had been a “worrying number of people in Scotland who tested positive for Covid-19 and who had returned from Greece”.

He added: “In the case of Portugal, it was unfortunate that the UK Government announced their decision yesterday before ministers from England, Scotland and Northern Ireland met and before considering the latest Joint Biosecurity Centre (JBC) data.

“This indicated a significant rise in both the prevalence of the virus in Portugal and in test positivity.”

Welsh health minister Vaughan Gething said Wales was acting “in line with” the risk assessments from the JBC in imposing a 14-day quarantine on arrivals from the six Greek islands and Portugal.

It comes as more areas in England were placed on the Government’s Covid watchlist.

Leeds, South Tyneside, Corby, Middlesbrough and Kettering have been added to the list of areas that ministers are concerned about, Health Secretary Matt Hancock confirmed.

Norfolk, Rossendale and Northampton will be added as “areas of enhanced support”, meaning the Government will work with local authorities to provide additional resources – such as testing or contact tracing – to help bring the numbers of infections down.

The Cabinet minister did, however, have better news for parts of Greater Manchester, Lancashire and West Yorkshire which have faced restrictions designed to control the spread of coronavirus in recent weeks.

Mr Hancock said pools, gyms and sports facilities will be allowed to open from Tuesday in the remaining areas of Blackburn with Darwen, Bradford and Leicester that were still under local lockdown conditions.

And casinos, skating rinks, bowling alleys, exhibition halls, conference centres, and indoor play areas will be able to lawfully reopen on the same day throughout Greater Manchester – apart from Bolton, where these restrictions will remain in place – Lancashire and West Yorkshire.

Newark and Sherwood, Slough and Wakefield will be removed as “areas of concern”, Mr Hancock confirmed.

Fears were raised, however, that the impending return of universities could make significant outbreaks of coronavirus “highly likely” and that such virus epicentres would risk amplifying the transmission of the virus across the country.

According to Government scientific advisers, social interactions and accommodation are likely to be a “high risk environment” for transmission to occur – and asymptomatic cases among students may make it harder to detect, they warned.

Students who are residents in university accommodation should be segmented as far as possible to co-locate courses or year groups, to minimise networks between different parts of an institution

In a document published by the Scientific Advisory Group for Emergencies (Sage), scientists have suggested that wider-scale testing, combined with action places, may help control campus outbreaks.

Wearing face coverings in campus buildings and reducing in-person interactions may mitigate the transmission of Covid-19, the advice suggests.

Sage said: “Students who are residents in university accommodation should be segmented as far as possible to co-locate courses or year groups, to minimise networks between different parts of an institution.”

The Government said there had been a further 1,940 daily lab-confirmed cases of coronavirus while a further 10 people had died in the UK within 28 days of testing positive for Covid-19 as of 9am on Friday.

Separate figures published by the UK’s statistics agencies show there have now been 57,300 deaths registered in the UK where Covid-19 was mentioned on the death certificate.