THERESA May has been accused of “treating Scotland with contempt” after it emerged that Scottish secretary David Mundell will only have a part-time place on the special cabinet committee planning the UK Government’s strategy on Brexit.

The Liberal Democrats accused the Prime Minister of being “dead-set on a hard Brexit” because every single cabinet minister of the six who campaigned to leave the EU has secured a place on the exiting the EU and trade committee.

No 10 declined to comment, saying the membership of the committee would be announced next week but leaked details showed that it would be split between six ministers, who backed Leave, and six, who backed Remain.

However, controversially, the territorial secretaries of state will only attend “as required” to do so by Mrs May.

Angus Robertson, the SNP’s new deputy leader, who leads the party at Westminster, said: "The revelation that the Scottish Secretary is not a full member of Theresa May's Brexit Cabinet committee is deeply embarrassing for David Mundell but more importantly it also seriously undermines her claim that Scotland will be fully involved in the Brexit negotiations.”

He went on: “The UK Government is treating Scotland with contempt. But make no mistake, the SNP will ensure that Scotland's voice is heard loudly and clearly in the Brexit process.”

Tim Farron for the Lib Dems said the “line-up of hard Brexiteers” was a further sign that the Tory Government was “dead set on a hard Brexit, putting jobs at risk and happy for costs to rise from our shelves to our petrol pumps”.

He added: “This is a case of May letting the foxes into the hen-house.”

Labour’s Chuka Ummuna, a prominent figure in the pro-single market Open Britain campaign, said that while it was encouraging to know there would be greater discussion at cabinet level, the Government needed to be much more open about the aims and principles of their Brexit negotiation.

“We should not be forced into a hard Brexit by a private cabal of ministers,” added the London MP.

The row over the cabinet committee broke out as Nissan chief executive Carlos Ghosn, who has warned that the Japanese car giant could halt new investment in Britain following the Brexit vote, had what appeared to be a successful meeting with the PM in Downing Street.

The car boss emerged, expressing confidence that Britain would remain a "competitive place to do business". He said he looked forward to having a “continued positive collaboration between Nissan and the UK Government".

Mr Ghosn had previously suggested the car giant would stop new investment in its factory in Sunderland unless it received a compensation deal from the UK Government for any adverse financial impact from the decision to leave the EU.

Following the No 10 meeting, the Prime Minister said: “This Government is committed to creating and supporting the right conditions for the automotive industry to go from strength to strength in the UK, now and into the future."

Keeping Nissan in the UK is regarded as vital to Mrs May's hopes for a successful Brexit. The Sunderland plant, which has been active since 1986, employs almost 7,000 people producing around 2,000 cars a day.

The Japanese giant is part-owned by French manufacturer Renault, raising concerns that production could be moved to France to avoid any tariffs, which could be introduced on exports to the EU if the UK left the single market.

Meantime, the PM also met Britain's ambassadors to the other 27 EU member states to discuss their assessment of the individual countries' attitudes to Brexit.

Mrs May set out her commitment to build strong post-Brexit relationships with each of the countries and told the ambassadors she intended to hold bilateral talks with each of the 27 heads of government by the time of the European Council summit in December.