“That does not mean to say that I want to be in a position of imposing these kinds of protections again.”

She again urged the public to be more vigilant in complying with existing rules, but added: “Will it be enough of a difference? We will only be able to know that when we learn more about this variant of the virus in the days to come.”

Cases have been detected in Essex and Nottingham and there is an assumption that the variant will be found in Scotland within days.

A third UK case was identified yesterday in an individual who had spent time in London but is no longer in the country.

Yesterday, Angelique Coetzee, the South African doctor who treated early cases of the omicron variant, claimed countries such as the UK were “panicking unnecessarily” about the variant and the symptoms she had seen were “extremely mild”.

However, speaking about international travel, Ms Sturgeon said: “I think we may have to go further on restricting travel in the days to come. I hope I’m wrong about that, but we must keep our minds open to that”.

Asked whether she would consider attempting to close the border with England, as she did earlier in the pandemic, she said this would be a “last resort” but added: “I think we need to be open minded to doing anything required to keep the population safe right now.” 

A spokesman for the Scottish Tories said: “Obviously the new variant has changed the situation around Covid but many people’s jobs and livelihoods depend on travelling freely between Scotland and England.

“It’s vital that any decisions are made once more information is available about this new variant.

“The government should carefully examine the possible impact of any restrictions before considering introducing them.”