The Secretary of State for Scotland, Alister Jack, is self-isolating after developing symptoms of coronavirus.
The Conservative MP for Dumfries and Galloway said he was experiencing "mild" symptoms, including a cough and a temperature, but had not been tested for Covid-19.
"In the past 24 hours, I have developed mild symptoms associated with coronavirus," Mr Jack said in a statement.
"In line with medical guidance, I am self-isolating and working from home," he added.
The 57-year-old has been at home in his constituency since Wednesday, having appeared on the front bench in the House of Commons with Prime Minister Boris Johnson earlier in the day.
The development comes after the Prime Minister and Health Secretary Matt Hancock confirmed on Friday they had both tested positive for Covid-19.
England's Chief Medical Officer, Professor Chris Whitty, also said that he has symptoms of the virus.
Mr Johnson, Mr Hancock and Mr Whitty are all self-isolating and continuing to work.
More than 14,500 confirmed cases of Covid-19 have now been recorded nationwide, with the overall death toll standing at 759.
