PRIME Minister Keir Starmer’s insistence that the UK is “rotten” and things will get worse is making it "difficult" to argue for the Union, a former Better Together adviser has said.

Paul Sinclair, a former senior adviser to Alistair Darling, also said that the No campaign had not won people’s hearts in 2014 – but only made them “think twice” about voting Yes.

Writing in The Guardian, Sinclair said: “We won the vote, but as a senior member of the Better Together team, I still doubt we won the campaign.

“Ten years of SNP rule at Holyrood since makes me conclude that we made Scots think twice, rather than win their hearts.”

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Sinclair noted that some people have said the Yes side has “wasted the past 10 years” because they cannot yet give satisfactory answers to the key questions that defined the 2014 campaign, such as on currency.

However, he added: “If that is the case, the pro-Union side has been just as lazy if our best arguments are still about what Scotland couldn’t do outside the Union – rather than what we can do because we are in it.

“Currently no one owns what I call the sense of ‘Scottish possibility’, and whoever does first will prevail.”

Sinclair went on: “In 1707 there was a positive case for the union in giving Scotland access to England’s global trade routes. In this era, we have Brexit.

“It is difficult to make the positive case for the Union when – however correctly – the new UK Prime Minister says the country is rotten and things are going to get worse.”

Keir Starmer has said things will get worse and warned of more cuts (Image: Isabel Infantes) The former Better Together adviser said that the pro-Union side needed to “regard Scotland as a sovereign state” in order to win the argument.

He was writing in The Guardian alongside some political experts who also gave their views 10 years on from the independence referendum which the No side won by 55% to 45%.

Professor Nicola McEwen, the director of the Centre for Public Policy at Glasgow University, said that “today, 45% appears to be a floor rather than a ceiling on independence support”.

She noted that there had been a general preference towards maximum devolution among the Scottish public, at least until the Brexit vote in 2016.

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Then, McEwen said that “even with devolution included, independence became the preferred option”.

“Independence support also became more closely aligned with remain support in the Brexit referendum.

“This may reflect the clear anti-Brexit stance of the SNP as much as seeing independence as a route back to EU membership.”

She finished: “Independence is far from being the ‘settled will’. But the same can be said of the Union.”