Theresa May has pledged to make a “positive, optimistic and passionate case” for the Union as she laid the ground for a second independence referendum.
The Prime Minister criticised her predecessors in Downing Street for adopting a “devolve and forget” attitude towards Scotland and vowed to become more involved in the Scottish Parliament’s responsibilities.
But she risked a furious row with the Scottish Government by dropping a heavy hint she will seek to rewrite the Scotland Act to ensure some powers over farming and fishing return to Westminster rather than Holyrood after Brexit.
Echoing the rhetoric of the 2014 campaign as she addressed the Scottish Conservative conference in Glasgow’s Scottish Event Campus, the UK Tory leader said independence “simply does not add up”, highlighting a decline in the drop in oil price, the currency and central bank.
Mrs May tried to make an argument aimed at Scots’ hearts as well as their heads, however, by describing the UK as “a union of people, affections and loyalties.”
She said: “One of the driving forces behind the Union’s creation was the remorseless logic that greater economic strength and security come from being united.
“Not the transient and shifting benefits of international alliance, but the fundamental strength of being one people. Those enduring economic strengths are obvious.”
The Prime Minister added: “The devolution of powers across the United Kingdom must not mean we become a looser and weaker union.
“We cannot allow our United Kingdom to drift apart. For too long the attitude in Whitehall has been to ‘devolve and forget’.
“But as Prime Minister of the United Kingdom, I am just as concerned that young people in Dundee get a good start in life and receive the education they need to reach their full potential as I am about young people in Doncaster and Dartford.”
First Minister Nicola Sturgeon has accused Ruth Davidson of endorsing a power and cash grab over agriculture responsibilities after the Scottish Conservative leader suggested Holyrood might not get control over farming subsidies once the UK leaves the European Union.
Rural affairs are devolved but Mrs May appeared to endorse this thought process, arguing that the devolution settlement did not consider a potential Brexit and arguing a single market around standards would best suit Scottish farmers.
She said: “As we bring powers and control back to the United Kingdom, we must ensure that right powers sit at the right level to ensure our United Kingdom can operate effectively and in the interests of all of its citizens, including people in Scotland.
“We must also ensure that the UK which emerges from the EU is able to strike the best possible trade deals internationally.”
Ms Sturgeon has said a second independence referendum is “highly likely” following the Brexit vote.
Angus Robertson, the SNP depute leader, argued the Scottish Government has a “cast-iron democratic mandate” for another vote.
He said: “This was an ironic, hypocritical and surreal speech from Theresa May, who before the EU referendum supported a campaign warning that leaving Europe would be a disaster, but is now determined to pull us over the cliff edge of an economically catastrophic hard Brexit.
“Theresa May is guilty of mind-boggling hypocrisy – it is her government’s constitutional obsession with a hard Brexit which is directly threatening Scottish jobs and livelihoods.
“In those circumstances, we have a duty to stand up for Scotland, and to have a plan in place to protect our vital national interests.”
Kezia Dugdale, the Scottish Labour leader, said: “The Prime Minister has undermined the Union at every turn since entering Downing Street.
“With her dangerous pursuit of a hard Brexit that threatens to harm our economy, Theresa May has created the deep divisions in our society that the SNP thrives upon.
“She may claim the Union is ‘precious’ to her, but the Prime Minister is the person responsible for putting the Union at risk once again.”