India has been added to the coronavirus “red list” in response to mounting concern about the number of cases there and the emergence of a variant.

The move, announced just hours after Boris Johnson was forced to cancel a trip to the country, comes into force at 4am on Friday, meaning Britons returning after that point will be forced to quarantine in a hotel for 10 days.

Anyone who is not a UK or Irish resident or a British citizen will be banned from entering the country if they have been in India in the previous 10 days.

READ MORE: Four cases of India Covid strain found in Scotland

Health Secretary Matt Hancock said so far 103 cases of the Indian variant had been identified in the UK.

Concern about variants of the disease – and whether existing vaccines will prove effective – has led to the Government ramping up plans for a campaign of booster shots later this year.

Mr Hancock told MPs: “We’ve recently seen a new variant first identified in India. We’ve now detected 103 cases of this variant, of which again the vast majority have links to international travel and have been picked up by our testing at the border.”

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Mr Hancock said the samples have been analysed to see if the new variant has any “concerning characteristics” such as greater transmissibility or resistance to treatments and vaccines.

He added: “After studying the data, and on a precautionary basis, we’ve made the difficult but vital decision to add India to the red list.”

Scottish Government Transport Secretary Michael Matheson said: “Scotland has strong, historic ties with India but we have taken this difficult decision after the Joint Biosecurity Centre increased its risk rating due to the high levels of in-country transmission and the threat posed from new variants.

“No one wants these restrictions in place any longer than necessary, but we have to take whatever steps are required to protect the public as we continue to emerge from lockdown in Scotland.

“International travel will continue to remain a significant risk, requiring a cautious approach, on a four-nation basis.”