More preventative action may be “necessary” to stop a faster-spreading strain of coronavirus taking hold, Nicola Sturgeon has said.
Her warning followed a meeting of representatives from the UK’s four nations to discuss the new strain.
The first minister added that the Scottish cabinet would meet on Saturday afternoon to discuss the situation.
The BBC understands Boris Johnson is about to announce tougher measures for London and south east England.
Cabinet sources said several areas may moved into a new fourth tier of restrictions, and plans to relax the rules over household mixing over Christmas would be changed.
In a tweet Nicola Sturgeon emphasised that cases were currently at a “lower level in Scotland than [the rest of the] UK”.
But she added: “Preventative action may be necessary to stop faster spreading strain taking hold.”
The warning comes as scientists continue to evaluate the spread of the new variant in south-east England, where there are “growing concerns” about its transmission.
The UK said it had now informed the World Health Organisation it had concluded the strain could spread more quickly.
On Wednesday, Ms Sturgeon confirmed nine cases of the new variant had been identified in Scotland.
The cases were all detected in the Greater Glasgow and Clyde health board area, and date back to the end of November.
The Scottish government has refused to rule out bringing in stricter measures after Christmas.
On Friday, it said “every possible option remains on the table” when the levels of restrictions are reviewed on Tuesday.
Wales and Northern Ireland have already announced post-Christmas lockdowns.
And Boris Johnson, who held an unscheduled meeting on Friday evening to discuss possible further measures, said he was “hoping to avoid” another national lockdown in England.
But he is due to hold a news conference later on Saturday – amid the rising number of cases in south-east England.
Before that, the prime minister was having a cabinet meeting to discuss what action to take over the new Covid variant.
On Monday, England’s health secretary, Matt Hancock, said the variant may be associated with the faster transmission of the virus in the South East but there was “nothing to suggest” it caused worse disease or that vaccines would no longer work.
Covid figures published at 14:00 on Saturday showed Scotland had recorded 41 new deaths and 572 positive tests in the past 24 hours.