THE First Minister has attacked David Mundell’s exclusion from a key meeting called by Theresa May to decide the nature of relationship the UK should have with the European Union.

Nicola Sturgeon highlighted the absence of the Scottish Secretary in a photograph on social media of the 14 members of the Brexit “war cabinet” as they sat around the table in Chequers ahead of eight hours of discussions on Thursday.

In a post on Twitter yesterday, she wrote: “The fact that decisions with massive implications for Scotland’s future are being taken behind closed doors at Chequers is bad enough ... but the fact that the Minister supposed to represent Scotland’s interests in the UK Gov isn’t even invited to the table beggars belief.”

Karen Bradley, the Northern Ireland Secretary, was invited to the meeting and was pictured sitting beside Foreign Secretary Boris Johnson.

Tommy Sheppard, the SNP’s spokesman on Scotland at Westminster, suggested the Northern Ireland Secretary got an invite because the DUP were propping up May’s Government. Arlene Foster’s party agreed to support the minority Conservative Government in return for £1 billion extra funds for Northern Ireland.

Sheppard said: “Given the implications of Brexit on devolution it shows a casual disregard of the nations of the UK for the Brexit cabinet to be assembled without any Scottish voice.

“To suggest Northern Ireland should get a representation on the Brexit war cabinet and Scotland doesn’t is adding insult to injury – and comes on top, of course, of the £1bn DUP bung.”

Following the meeting, Downing Street said May will deliver a long-awaited speech setting out her vision for the UK’s future relationship with the EU next Friday.

The announcement was made yesterday after it emerged Eurosceptic ministers were said to have won an internal debate over what sort of Brexit the UK Government would pursue.

May gathered her deeply divided Cabinet for an away day at Chequers on Thursday, where they attempted to achieve a united position.

European Council president Donald Tusk last night dismissed what they had come up with as “pure illusion”.

Reports yesterday morning suggested that after the meeting broke up at 10pm, senior sources claimed that “divergence has won”, meaning the UK will demand being able to remove EU protections and safeguards – such as the working time directive and paid annual leave – after it quits the bloc.

Hardline Brexiteers such as Foreign Secretary Boris Johnson and International Trade Secretary Liam Fox strongly support the UK from being able to diverge from EU regulations.

However, pro-Remain ministers, such as Chancellor Philip Hammond and Home Secretary Amber Rudd, had argued the UK should stick as closely as possible to European laws to avoid causing unnecessary damage to the economy.

In a major compromise aimed at helping to smooth over the deep divisions, the meeting refused to put a precise timetable on when Britain would fully allow regulatory divergence.

Health Secretary Jeremy Hunt – who was not at the Chequers meeting – said the Government will pursue a policy putting Britain outside a customs union with the EU but matching Brussels rules in certain sectors in an attempt to achieve “frictionless” trade.

The policy puts May on a collision course with Tory Remainers who are backing an amendment to the Trade Bill which would require the UK to form a customs union with Brussels on leaving the EU.

Tusk, who will have talks with May in London on Thursday, told a news conference last night that it appeared the UK still wanted to have its cake and eat it. He said: “I am glad that the UK Government seems to be moving towards a more detailed position. However, if the media reports are correct, I am afraid that the UK position today is based on pure illusion.

“It looks like the cake philosophy is still alive. From the very start it has been a key principle of the EU27 that there can be no cherry-picking and no single market a la carte.”

Meanwhile, it is widely predicted that Labour leader Jeremy Corbyn will give his blessing to a customs union arrangement with the EU in a speech on Monday, when he is expected to give more clarity on his party’s Brexit policy.

May’s speech is expected to take place in the UK, unlike previous keynote Brexit addresses in Florence and Munich, but Downing Street refused to discuss the venue.

She is expected to speak to the Scottish Tory conference in Aberdeen, which takes place on Friday and Saturday, but is not expected deliver her Brexit speech there.

Downing Street refused to comment on Sturgeon’s intervention.