SNP's Westminster leader Ian Blackford has said that Prime Minister Boris Johnson should sack chief aid Dominic Cummings after it emerged he travelled 250 miles to visit family during lockdown.

Speaking on the BBC’s Breakfast programme on Saturday morning, Mr Blackford said that the revelations were “extraordinary” and called on the Prime Minister to remove Mr Cummings from his position.

According to a joint investigation by the Daily Mirror and the Guardian, at the same time as the UK Government was instructing people to remain home - with fines in place for those contravening the rules - Mr Cummings decided to escape the capital.

Ian Blackford calls for sacking of Dominic Cummings

He is said to have been present at his family home when police from Durham Constabulary turned up on March 31, following a call from someone reporting they had seen Mr Cummings in the area.

Durham police confirmed officers had spoken to the owners of an address after reports a person had travelled there from London.

Mr Blackford said: “Dominic Cummings should have resigned. Now that he hasn’t, Boris Johnson must show leadership and must remove him from office immediately.

“I think it’s quite extraordinary what we have heard overnight.

“This is a huge story and it really begs the question when the Prime Minister knew about this? Why has there been a cover up and why haven’t we been told about this?

“Quite simply, on the basis of what everyone is doing by observing the rules to stay at home, protect theNHS and save lives, why the Prime Minister’s chief aid thought it was acceptable to drive hundreds of miles to be with his children’s grandparents in Durham.

“It does create this image of there is one rule for the rich and the powerful and one rule for everyone else. Rightly people will be outraged by this.”

When asked if he thought it was natural for parents to want to protect their children, Mr Blackford said: “Of course a parent wants to make sure their children are looked after..

“Remember it was the Prime Minister who went on the TV and said we need to protect the vulnerable and elderly and that we shouldn’t be visiting parents and grandparents.

“This is a clear breach of Boris Johnson’s own advice that was given to each and every one of us.”

A spokesperson for Durham Constabulary said: “On Tuesday, March 31, our officers were made aware of reports that an individual had travelled from London to Durham and was present at an address in the city.

"Officers made contact with the owners of that address who confirmed that the individual in question was present and was self-isolating in part of the house.

"In line with national policing guidance, officers explained to the family the arrangements around self-isolation guidelines and reiterated the appropriate advice around essential travel."

Other political leaders have piled pressure on Mr Johnson to sack the 48-year-old strategist for flouting the rules.

Former Conservative MP David Lidington, who was de facto deputy PM under Theresa May, was among those saying the news raised serious questions.

He told BBC Newsnight: "There's clearly serious questions that No 10 are going to have to address not least because the readiness of members of the public to follow government guidance more generally is going to be affected by this sort of story."

Sir Ed Davey, acting leader of the Liberal Democrats, called for Mr Cummings to quit over the allegations, while a spokesman for Labour said: "The British people do not expect there to be one rule for them and another rule for Dominic Cummings."

But friends of Mr Cummings suggested he would be going nowhere.

One told the PA news agency: "He isn't remotely bothered by this story, it's more fake news from the Guardian.

"There is zero chance of him resigning."

Last month, Catherine Calderwood, Scotland’s former Chief Medical Officer was forced to give up the post after being photographed ignoring her own advice by travelling from Edinburgh to her second home in Fife.

Downing Street has so far refused to comment.

'Boris Johnson must show leadership and must remove him from office immediately' - Ian Blackford calls for sacking of Dominic Cummings