Alastair Campbell has revealed that after being a “full-on” No campaigner ahead of the Scottish independence referendum in 2014, he is now “less certain”.

The revelation comes in with the publication of extracts from his diaries from 2010 to 2015, which exposes the turmoil behind the scenes of the campaign to keep Scotland in the union.

Tony Blair’s former spin chief also reveals that Alex Salmond offered him a place on his “negotiating team” in the event of Scotland becoming independent.

He said that came at a hotel in Aberdeen, where he was interviewing Salmond for GQ magazine.

The National: First Minister Alex Salmond will be speaking at the North East Economic Forum

Campbell said he was more impressed with the then SNP leader than he wanted to be.

“He was very friendly and warm and also less sneery and narky than usual,” he said.

“He was interesting for the book as well on winning and how he had changed his mind-set from one of opposition to one of government.

“He had read my blogs, knew about my family, talked up my being Scottish, asked me to stay for a long lunch and then most surprisingly of all asked me to be part of the negotiating team with the rest of the UK, Europe etc if he won.

“He seemed quite serious too. He said if they got independence he would want to reach out to people like me, and use the skills I had in government, and also nation branding.”

A book on the diaries is due to be published this month, but the extracts have been obtained by DCT Media, and published in the Dundee Courier and Aberdeen Press & Journal.

READ MORE: Nicola Sturgeon hits out after leak of Alex Salmond inquiry report

“I suspect I am not alone in feeling that English nationalism and global populism are a big part of what fuelled both Brexit and Johnson, which in turn has helped the SNP’s cause too,” Campbell wrote.

“It is not at all fanciful to imagine that in ‘taking back control’ through Brexit, Johnson will break the union in at least two parts, Scotland and Northern Ireland.”

In an introduction to the diaries, he added: “From being a full-on ‘No’ campaigner in 2014, it’s fair to say I am now less certain.”