SCOTTISH Deputy First Minister Kate Forbes’s views on equal marriage were branded as “archaic” and “quite extreme” by a former colleague today.

Former Paisley and Renfrewshire South MP and one-time deputy leader of the SNP’s Westminster group Mhairi Black made the remarks as she promoted her new venture, a run of shows entitled Politics Isn’t for Me at August’s Edinburgh Fringe.

Taking a swipe at Ms Forbes, who narrowly lost out to Humza Yousaf in last year’s leadership contest before being appointed deputy first minister by his successor, Ms Black told the Sunday Post Newspaper: “We all remember Kate Forbes’ interview where she said she wouldn’t have supported gay marriage and doesn’t think people should have kids out of wedlock.

“Basically really archaic and, in my opinion, quite extreme views.”

Speculation has mounted over John Swinney’s future as SNP leader after its general election drubbing, with some prominent Scottish nationalists, such as former MPs Joanna Cherry and Jim Sillars not only calling for his resignation but suggesting Ms Forbes step up into the role.

Ms Black appeared keen to kick these suggestions into touch, saying: “If you then start endorsing the sort of views Kate Forbes was saying, voluntarily, on camera, then that’s a massive red flag to so many people — particularly young people.

“The truth is independence won’t happen without young people and certainly support for the SNP and success for the SNP won’t happen without young people on board.

“Basically, the party needs to get its house in order, and that’s not going to happen unless there is real commitment to it and the leader is making it happen.”

An SNP spokeswoman said: “The SNP has consistently been a moderate, left-of-centre political party that is resolutely focused on delivering for the people of Scotland.”