Boris Johnson will not be self-isolating despite a member of his team on the recent visit to Scotland testing positive for Covid, Downing Street has said.
However, Mr Johnson could yet be told to stay at home, with Scottish contact tracers expected to be mapping out the interactions of the person involved.
The Telegraph understands the person who caught the virus was a junior civil servant working with the advance party for the Prime Minister.
The individual is understood to have been with him on a plane journey between Glasgow and Aberdeenshire on Wednesday. On Friday, a Downing Street source argued that the pair had sat at opposite ends of the plane and that the usual contact tracing rules apply on aircraft.
Thousands of other Britons have been forced to self-isolate after being pinged because someone on their flight caught Covid. A Number 10 source insisted Mr Johnson still had the NHS Covid app that alerts people to potential contacts with those who have been infected.
It is believed that when Michael Gove, the Cabinet Office minister, was ordered to self-isolate after a trip to Portugal to watch the Champions League final it was because someone on his flight home had tested positive. Mr Gove ultimately avoided self-isolation because he took part in a trial that allowed him to take daily Covid tests instead.
A Number 10 spokesman said: "The Prime Minister regularly visits communities across the UK, and all aspects of visits are carried out in line with Covid guidance. The Prime Minister has not come into close contact with anyone who has tested positive."
Mr Johnson visited Scotland on Wednesday and Thursday – his first trip north of the border for around six months – amid SNP calls for a second independence referendum.
The civil servant who later tested positive was present when he visited Police Scotland’s Tulliallan training college in Fife on Wednesday, according to Tory Party and government sources. The official is understood to have taken a Covid test on Wednesday and flown to Aberdeenshire later that day but only received the positive result on Thursday.
A Downing Street source said Mr Johnson was aware of the positive test before travelling back south but did not need to self-isolate given he was not in close contact. On Friday, he attended the Sovereign’s Parade at the Royal Military Academy Sandhurst, and is Chequers.
NHS Scotland’s Test and Protect team contact traces people who test positive in Scotland. A Scottish government spokesman did not comment when asked for an update on this case.
If Mr Johnson is told to self-isolate it will be the second time he has done so in a month after spending 10 days quarantining at Chequers following Sajid Javid’s positive test in mid-July.
The Prime Minister initially attempted to avoid self-isolation by taking part in a trial which allowed for daily testing instead before back-tracking after a public backlash.
Anneliese Dodds, the Labour party chairman, said it was clear that Mr Johnson "hasn’t learned anything from what happened last time he tried to cook up a reason to be above the rules everyone else has to follow".
The Covid rules in England change on August 16, when people with two Covid jabs will not have to self-isolate if pinged, with a test advised instead. Mr Johnson has rejected calls to bring forward the date.
Kwasi Kwarteng, the Business Secretary, Alister Jack, the Scottish Secretary and Douglas Ross, the Scottish Conservative leader, were all present at points for Mr Johnson’s Scottish visit, but none are believed to have been pinged or be self-isolating.