Work and Pensions Secretary Stephen Crabb insisted “a UK without Scotland is not the UK” as he launched his bid for the Tory leadership yesterday.
The Inverness-born frontbencher, who previously served as Welsh secretary, was the first to announce his candidacy in the race to become the next prime minister.
He is expected to face competition from Home Secretary Theresa May and former London mayor Boris Johnson, among others.
Last night, sources close to former defence secretary Liam Fox confirmed he would run again, having lost to David Cameron in 2005.
Pitching himself as the unity candidate, Mr Crabb, 43, said: “I really worry about the future of our divided UK.
“A UK without Scotland is not the UK, a Great Britain without Scotland is not Great Britain.
“I worry about the divided society and about the breakdown in trust among those who are really struggling at this time.”
Describing his upbringing, he said he was born in Scotland before moving to Wales, where he had a “fabulous education at a really good comprehensive school across the road from the council house where I lived”.
It was a clear attempt to highlight the differences between himself and Mr Johnson, who attended Eton.
In a further swipe at the latter’s previous comments on the leadership, he added: “On the rainy rugby fields of West Wales I learned that it is not a question of waiting for the ball to pop out of the back of the scrum.”
The Welsh MP campaigned for the UK to stay in the European Union, but was keen to stress the leadership race should not be defined by divisive labels such as Remainer and Brexiteer.
He said there was no question of a second referendum on membership, adding that he would get on with implementing the decision of the 17 million people who backed Vote Leave.
“Brexit needs to do what it says on the tin,” he added.
Outlining the principles that would guide his negotiation of the UK’s new relationship with the EU, he said controlling immigration would be a red line issue.
Mr Crabb also revealed he would create an advisory council to bring together governments and assemblies from across the country.
Asked about his vote against same-sex marriage in 2013, Mr Crabb insisted he was “absolutely not” prejudiced against gay people.
Introducing the launch, Business Secretary Sajid Javid confirmed the joint ticket meant he would become chancellor in a Crabb premiership.
