Prime minister Boris Johnson has once again taken aim at the performance of Scottish education.

He cited Scotland’s performance in the Pisa (Programme for International Student Assessment) rankings as evidence of decline in Scotland.

The prime minister said: “Look, I mean Scottish education is legendary: it produced Michael Gove, the Chancellor of the Duchy of Lancaster...[broadcaster] Andrew Neil is a product of of the Scottish [system], thinking of someone entirely at random.

Previously: PM criticises Scottish education’s ‘grave inadequacies’

Sturgeon vs Gove: First minister hits back at criticism from Michael Gove

Analysis: What does Pisa tell us about Scottish education?

Pisa results: Is Scotland ‘stagnating in mediocrity’?

“It’s a fantastic system, but recently Scotland, through no fault of the pupils, has been slipping down the Pisa rankings, both for maths and science, and I think it’s time the SNP really focused on the priorities of the people of Scotland - on education, on healthcare, on cutting drug addiction - rather than on breaking up the union in the UK, with no really clear idea about how it would work.”

Mr Johnson made his comments during the latest “People’s PMQs” (Prime Minister’s Questions), an initiative he introduced last year in which he answers questions from pre-selected members of the public.

In an analysis of Pisa data, University of Stirling academics Mark Priestley and Marina Shapira said in December that “the media hype about Scotland’s decline in maths and science is not especially warranted, as the evidence is actually pretty underwhelming”.

However, the University of Edinburgh’s Lindsay Paterson said: “Scotland’s overall performance [in Pisa] is best described as stagnating in mediocrity.”

In response to Mr Johnson’s latest comment, a Scottish government spokesperson said: “Most recent Pisa data showed Scotland’s maths and science scores are stable at the OECD (Organisation for Economic Cooperation and Development) average, while reading levels rose sharply.”

In response to the prime minister’s previous criticism of Scottish education, in September, SNP depute leader Keith Brown said: “The last thing Scotland needs or wants is an ill-informed lecture like this from Boris Johnson.”

Mr Brown added: “People across Scotland are looking on in horror at the chaos engulfing Westminster and the Brexit disaster being imposed on Scotland by Boris Johnson and his extremist cabal in Downing Street.”