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”, and has warned that Boris Johnson will “break the Union”.

The revelations come in a serialisation of extracts from his diaries from 2010 to 2015, which exposes the turmoil behind the scenes of the campaign to keep Scotland in the UK.

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

He said that offer was made during a meeting at the Marcliffe Hotel in Aberdeen, where he was interviewing Salmond for GQ magazine.

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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,” said Campbell.

“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.”

Campbell added: “He clearly didn’t rate [David] Cameron. Loathed [George] Osborne. Not impressed by Ed [Miliband].

“My sense was he really thought he could win.”

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In the GQ interview Salmond made some comments appearing to approve of Russian leader Vladimir Putin, as well as some “loose” remarks on Scotland’s reputation with alcohol.

They caused a storm when the interview was published and Salmond later defended what he had said about Putin restoring pride in Russia.

“I said I deprecated Russian actions in Ukraine and also its human rights record,” he said. “I pointed out that the Western press underestimated Putin and that’s obviously true.”

However, Campbell said the “furore” had no impact on the job Salmond offered him, as he wrote in a May 5 entry: “Meanwhile Labour and the Better Together people were loving it because it had him on the back foot for the first time in ages.

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“He had asked me to be part of his negotiation team if he won, and one of his people told me that was a serious proposition, and the furore did not change that. ‘If anything it makes him keener, because it shows you can still get a message up, even at his expense’.”

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.

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

He warned that Boris Johnson could break the Union in at least two parts: “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.”