Philip Hammond, UK defence secretary, has ridiculed Scottish nationalist plans for an independent military, insisting Scotland would be less secure if it votes in September to end its three century-old political union with England.
Seeking to rally Scottish Conservatives at the party’s spring conference in Edinburgh, Mr Hammond said a small country could not match the UK’s range of defence capabilities and that independence would put at risk Scotland’s defence industry.
David Cameron, UK prime minister, on Friday told the Scottish party his big message was to avoid negativity in the referendum campaign and focus on making a “big, generous, positive argument for the UK”.
However, other senior UK ministers have sought to stress the difficulties an independent Scotland would face.
Mr Hammond said the £2.5bn annual defence budget suggested by the Scottish National party could not provide the security Scotland currently enjoyed and leaving the UK could threaten 12,600 Scottish defence sector jobs.
“When the separatists talk about maintaining warship building in Scotland to meet the needs of a separate Scotland they are either deluded, or they are seeking to delude,” the defence secretary said.
BAE Systems last year announced it would close its shipbuilding yard in Portsmouth to focus on the Clyde, but ministers suggest the UK would never give orders for large complex warships to a foreign country.
The Scottish government insists that after independence the Clyde would still be the best place for the UK to build warships and that future joint procurement of frigates to be built there would be in the interest of both sides.
In a speech on Friday, Theresa May, UK home secretary, also focused on the risks of independence, raising the threat of London imposing border controls if Edinburgh tried to adopt a more welcoming policy on immigration.
The Scottish government has said easing restrictions on immigration would be an important way of boosting the economy and addressing the challenge of a relatively rapidly ageing population.
But Ms May said looser immigration policy would undermine the UK coalition government’s work to reduce the number of people coming to work and live in the UK.
“The continuing UK could not allow Scotland to become a convenient landing point for migration into the United Kingdom,” she said. “So that would mean border controls between a separate Scotland and the United Kingdom -- passport checks to visit friends and relatives.”
Scottish National party leaders have dismissed the threat of border controls as an example of pro-union political scaremongering, noting that none are imposed between the UK and Ireland.
Ms May also insisted independence would mean Scotland losing its membership of the EU, leaving it forced to go “cap in hand to beg for admission”.
SNP leaders now accept that entry to the EU would have to be negotiated, but say it will be welcomed as a wealthy and resource-rich nation that already accords with European law.