MHAIRI Black has expressed her shock at receiving a “straightforward” answer from David Mundell during Scottish questions in the House of Commons.

The SNP MP took to Twitter to express her surprise after probing the Scottish Secretary on comments made by Boris Johnson.

The favourite to replace Theresa May as prime minister wrote in The Spectator In 2005 that it would be “utterly outrageous” if Gordon Brown succeeded Tony Blair, adding: “… mainly because he is a Scot, and government by a Scot is just not conceivable in the current constitutional context.”

READ MORE: Boris Johnson says idea of a Scottish prime minister is 'utterly outrageous'

Black put these comments to Mundell in the Commons.

She said: “The current frontrunner to become prime minister has said that ‘government by a scot is just no conceivable in the current constitutional context.

“Does the Secretary of State agree with this opinion and does he believe that such an opinion is helpful to inter-governmental relations?”

The Scottish Secretary responded by speculating about Black’s own political ambitions.

“Eh … I … don’t agree with that and I’m sure the honourable member for East Dunbartonshire aspires to the office of prime minister should she lead her party,” he replied.

“So no I don’t agree with that analysis.”

Reacting to the exchange on Twitter afterwards, Black said: “Genuinely shocked I got a straightforward answer.”