DAVID Cameron has said he offered to attend the Scottish Parliament annually for scrutiny while Prime Minister, but the offer was never taken up.

In written evidence to a Westminster committee, submitted weeks before his dramatic return to government on Monday, the former prime minister said his “respect agenda” helped to deliver a better deal for Scotland.

The submission from the newly minted "Lord Cameron", along with another from Tony Blair, was published by the Scottish Affairs Committee on Monday.

The committee is examining the state of intergovernmental relations over the past 25 years since devolution was introduced.

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Both former leaders sought to describe how relations between Westminster and Edinburgh developed during their time in office.

In a letter written before September 21 this year, Cameron said he had attempted to repair “poor” relations when he became prime minister – reinstating formal channels of communication under his “respect agenda”.

He said: “I also made an offer to appear once as year as prime minister before the Scottish Parliament.

“Although that offer was not taken up, I believed that the overall engagement vastly improved and, above all, allowed us to deliver a better deal for Scotland.”

Cameron (below) pointed to the deal which led to the 2014 Scottish independence referendum – where Holyrood was granted powers to conduct the vote – as evidence of his approach working.

The National: David Cameron returns to the Cabinet (James Manning/PA)

He said: “For the result to hold, and be accepted, the referendum should be ‘made in Scotland’.

“It was, and the question of Scottish independence was settled for a generation.”

In Blair’s submission, the former Labour leader said he “never expected that devolution would end the campaign for separatism” but rather that it would limit its appeal.

Polling consistently shows devolution is more popular in Scotland than independence, he said.

He said: “The result of the 2014 referendum was clear in favouring remain and, were it not for Brexit, would have put the issue to bed for a generation.

“As I say above, the test for the reforms should not be whether the separatist voices have disappeared, but whether they have prevailed. And to date, they have not.”

On Monday, the Scottish Affairs Committee heard from a number of former ministers who were involved in devolution policy.

Scottish Conservative leader and MP Douglas Ross referred to Cameron’s evidence during the meeting, saying it was “unfortunate” the former prime minister’s offer was never accepted.

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One of those giving evidence was Lord George Robertson, who famously said devolution would kill Scottish nationalism “stone dead”.

When SNP MP and committee chair Pete Wishart quizzed him on this, he said: “Respectfully Mr Chairman, I have yet to be proved wrong.”

He added: “It wasn’t a prophecy that was designed at that precise moment to say it was going to happen instantaneously.”

Lord Andrew Dunlop, a former special adviser to Cameron’s government, said he did not know why the offer to the Scottish Parliament had not been taken up but it was a “good idea and perhaps something that should be thought about again”.