Among his suggestions is the setting of legal parameters for another referendum to be held.
“There needs to be clarity on the terms of a referendum – clarity which reflects the reality that it is wholly exceptional for states to allow their own dissolution,” he wrote in the Daily Telegraph.
“Of course, any government would have to respect the settled will of an overwhelming majority in Scotland to govern themselves. But those terms have to be defined.
“I would suggest 75% of seats in the Scottish Parliament in favour of independence, over a 10-year period, legally binding. Without that, a referendum should simply be impossible.”
The Scottish Government is currently seeking to legislate in Holyrood for another referendum, with the Lord Advocate asking the UK Supreme Court to rule whether a draft Bill is within the legislative competence of the Scottish Parliament.
Among Lord Frost’s other suggestions is to change the language around the union, saying “we have all drifted into speaking as if this country were already a confederation made up of four ‘nations’ that have chosen to work together”.
He added: “The Scottish ‘government’ is not the government of a state in confederation with England.
“It is a subordinate entity within the UK, with powers granted to it by the UK Government and Parliament, and ultimately subject to the supremacy of that Parliament.
“SNP activists hate it when you remind them of this. All the more need to do so.”
He also urged those in England to protect the union.
“I urge people in England not to give in to the ‘let them go’ argument,” he said.
“Partly because the break-up of the country would be a massive national humiliation.
“In Europe and beyond, it would be seen as a comeuppance which they would exploit to the full. But, more importantly, because it is morally wrong.
“Supporters of the union in Scotland, people who have built their lives and families on the assumption of its permanence, should not be abandoned.
“The UK is everyone’s country and we must protect and support it.”
Lord Frost’s comments outraged SNP Scotland spokeswoman Mhairi Black, who called on Tory leadership candidate Liz Truss to rule out his appointment to her government.
“Lord Frost’s comments are a disgrace and fly completely in the face of the longstanding position unionists have supposedly held that Scotland is an ‘equal partner’ within the UK – a promise continually made before the 2014 referendum by the anti-independence campaign,” she said.
“His comments not only fly in the face of a decades long held position but, like Brexit, disrespect the vote in 2014.
“Frost’s comments expose the ugly reality beneath Tory rhetoric around Scotland being a valued partner and show that under Truss there will be a concerted plot to dismantle the devolution settlement the Scottish people voted for overwhelmingly 25 years ago.
“That move will be resisted at every turn by the SNP and increasingly by civic Scotland and the people of this nation.”