THERE was ‘panic’ among No campaigners in the run up to the 2014 independence referendum after a secret poll put Yes 4% ahead.

The poll was carried out by the UK Government just days before Scots cat their vote, with the No campaign going on to win by 55% to 45%.

The shocking revelation, published on the BBC News website today, will be broadcast during the third part part of the documentary series Yes/No: Inside the Indyref on Tuesday, which looks at the final days of the campaign.

In it, Andrew Dunlop, special advisor the then Prime Minister David Cameron, said that the Government was so concerned about the shift in attitude towards independence that it conducted its own poll.

Less than two weeks before the vote, the secret poll found that Yes was 4% ahead.

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The result caused “overwhelming panic” among Unionists according to Ruth Davidson, and plans were subsequently put in place to change the approach of the No campaign.

The Yes movement was given little to no chance by most commentators when the campaign kicked off, with Better Together 20 points ahead in the polls.

That margin was reduced significantly during the course of the campaign, with a YouGov poll – published on the same day the UK Government conducted its secret poll – putting Yes ahead by two points.

That prompted the leaders of the main UK parties to put on a united front and promise Scotland more powers through the much-publicised Vow.

However, hopes of “home rule”, “devo max” and “near federalism” for Scotland were dashed within 24 hours of the vote when Cameron announced plans to fast-track proposals to prevent Scottish MPs voting on English law, with no reference to the Vow.

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The latest episode also includes an interview with veteran BBC broadcaster Allan Little, who criticises the attitude of some of his London-based colleagues, as well as a look back at the high-profile dispute between then first minister Alex Salmond and BBC journalist Nick Robinson.

Yes/No: Inside the Indyref will be broadcast at 10pm on Tuesday on BBC Scotland