BORIS Johnson has been accused of handing a “gift” to the SNP after jetting off to Marbella without appointing a new devolution minister.

The Prime Minister undertook a significant cabinet reshuffle last month, moving minister for the Constitution and Devolution Chloe Smith to the Department of Work and Pensions.

HeraldScotland: Official UK Parliament portrait of Chloe Smith, MP for Norwich North.

Ms Smith had worked in constitutional policy areas for some time, with her duties including working with Michael Gove to “strengthen the Union” and drive “the government’s devolution agenda”.

However the post is now lying vacant with no new announcements coming from the office since September 15 - the day before the reshuffle.

HeraldScotland: No role-holder is displayed for the Minister for the Constitution and Devolution since Chloe Smith left last monthNo role-holder is displayed for the Minister for the Constitution and Devolution since Chloe Smith left last month

The apparent oversight is an own goal for the SNP, Labour peer George Foulkes has said, and a massive error of judgement for the self-styled ‘Minister for the Union’ Mr Johnson.

Scottish Conservative sources have also told The Herald the failure to replace Ms Smith was “embarrassing, and probably something No.10 hoped nobody would notice”.

Combined with the sacking of David Duguid, junior Scotland Office Minister, only to replace him with unelected Tory donor Malcolm Offord, the oversight is believed to have added to growing friction between the Scottish and UK Conservatives.

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Party sources say the Prime Minister is “not helping” the Scottish Tories’ hopes of trying to oust Nicola Sturgeon and the SNP at the next election, despite their attempts to rebrand themselves as the party for working class Scots who are serious about protecting the union.

Lord Foulkes said the oversight was “appalling” and it showed the Prime Minister had no regard for the constitution or improving it.

His comments come as it emerged Mr Johnson has flown off to Spain for a luxury break with his wife Carrie, amid a growing crisis over energy and food supplies and supply chain issues.

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Lord Foulkes has tabled a question in the Lords next week on the matter, demanding an update from the UK Government on who will replace Ms Smith.

The Labour peer said: “Bungling Boris has overlooked the important area of the Constitution and Devolution in his botched reshuffle.

“This is a gift to the SNP who will add it to their grievance agenda but it is also infuriating for those of us who think a new Constitutional settlement is one of the key issues we face in modernising the United Kingdom.”

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He said that members of the Common Frameworks Scrutiny Committee - which examines how legislation is operating following Brexit, in areas which used to be controlled by the EU but have now been ‘repatriated’ to the UK – had previously worked “closely” with Ms Smith.

He said: “Members of the Common Frameworks Scrutiny Committee, who include Lords Hope, Keen, Bruce and me, have been working closely with Chloe Smith in trying to find an agreed way forward with the UK and devolved authorities on powers transferred from the EU.

“We are astonished at this appalling oversight.”

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Ian Murray, Labour’s Shadow Scotland minister added: “Boris Johnson’s incompetence is endless.

“The SNP might be the ones driving the separatist campaign but the Tories are the biggest threat to the union.

“While the Tories and the SNP play their petty constitutional games, Labour are focussed on building a progressive future for every part of the U.K.”

HeraldScotland: Kirsten Oswald speaks in the House of Commons

The SNP’s Kirsten Oswald MP added: “The UK government is asleep at the wheel. The Prime Minister rebranded himself as Minister for the Union - it’s clear now that he has either forgotten that devolution exists or has confirmed it’s not a priority.

“Successive Westminster governments have made it clear that Scotland is not a priority - or indeed a consideration - in the corridors of Whitehall.

The UK Government said Michael Gove has the responsibilities held by Ms Smith, and that strengthening the union and levelling up were key priorities.

A spokeswoman said: "The Rt Hon Michael Gove MP retains ministerial responsibility for the Union, Devolution and elections within his new role as Secretary of State for Levelling Up, Housing and Communities.

"Ministers and officials at all levels of government continue to work closely with the devolved administrations to give power to people and places across the UK, empowering our regions by devolving money, resources and control away from Westminster."