Scottish nationalists issued a new threat to Brexit today as they said the 'hugely significant' deal offered to Nissan showed Scotland could be given its own special deal to stay in the EU's single market.

Business Secretary Greg Clark revealed today he had promised Nissan the Government will fight for tariff-free access for the car industry.

He said his objective would be to secure a deal 'without tariffs and without bureaucratic impediments' for the automotive industry.

The SNP said the Nissan deal showed the Government is open to the principle of a 'flexible Brexit'.

First Minister Nicola Sturgeon is desperate to keep Scotland in the single market after Scots voted 62-38 per cent in favour of remaining in the EU in the referendum.

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First Minister Nicola Sturgeon and her Scottish Brexit minister Michael Russell (pictured together in Downing Street last week) are desperate to keep Scotland in the EU's single market and said the Government's 'special' deal with Nissan showed a 'flexible Brexit' was possible

Britain will pursue a tariff-free deal for the car industry in Brexit negotiations with the EU, Business Secretary Greg Clark (pictured on the Andrew Marr Show) revealed today

Her Brexit minister Michael Russell said: 'The Nissan deal is a hugely significant concession by the UK government because it shows they are open to the principle of a flexible Brexit.'

Mr Clark's comments suggest the Government is looking at the possibility of keeping certain industries - including the automotive sector - in Europe's single market.

He let slip about the Government Brexit strategy as he revealed the assurances that had persuaded Nissan to stay in the UK.

The Business Secretary said the car giant decided to pour new investment into its Sunderland plant after he reassured its board last week that the Government will be seeking a 'constructive and civilised dialogue' with the other 27 EU member states'.

He said his objective would be to secure a deal 'without tariffs and without bureaucratic impediments' for the automotive industry.

It contradicts statements by other government ministers, including Scotland Secretary David Mundell, who told Scottish lawmakers last week: 'If we are leaving the EU, we are leaving the single market.'

First Minister Nicola Sturgeon (left) has told Theresa May (right) that Scotland's overwhelming support for staying in the EU must be reflected in the final Brexit deal she secures with the EU

Nissan announced it is building two new models at its Sunderland plant after receiving assurances from the Government about post-Brexit Britain

The SNP's Mr Russell said today: 'David Mundell [said] there would be no special deal for Scotland - but he has been completely undermined by Theresa May's actions over the Nissan deal.

'It can't be right for the UK government to conclude backroom deals with some specific companies ... while pursuing a course of action that will cost many thousands of Scottish jobs.'

REVEALED: 42,000 UK JOBS WOULD HAVE BEEN LOST IF NISSAN LEFT BRITAIN Nissan employs 6,000 at its Sunderland plant, but the report warned that tens of thousands more jobs were at risk A bombshell report warning that 42,000 jobs would be lost if Nissan pulled out of Britain was handed to Ministers just before the Japanese car giant announced last week it was staying. One source who saw the contents said 'hair went up on end' when the Government saw the findings. Nissan employs 6,000 at its Sunderland plant, but the report warned that tens of thousands more jobs were at risk. Companies supplying Nissan in the UK employ 27,000 people – mostly in the North East. Other jobs indirectly dependent on the Sunderland plant took the total to 42,000. The report, written by Professor Garel Rhys, Emeritus Professor of Motor Industry Economics at Cardiff Business School, was shown to Ministers two weeks ago. The source said: 'The Government couldn't actually take the risk of calling Nissan's bluff. The balance of probability is that they could have stayed. But you can't guarantee that and it would be an economic catastrophe in the North East.' Advertisement

Ministers have been under pressure to explain what deal the company was given after chief executive Carlos Ghosn announced it was to build two new models in Sunderland after receiving 'support and assurances' from the Government.

Labour went as far as to question whether Mr Clark had offered Nissan 'bribes' to stay in the UK after Brexit.

But giving details about the assurances given to Nissan, Mr Clark told the Andrew Marr Show: 'What I said was that our objective would be to ensure that we would have continued access to the markets in Europe - and vice versa - without tariffs and without bureaucratic impediments and that is how we will approach those negotiations.

'For the continental European car manufacturers, they export a lot to us, we export a lot to them, components go backwards and forwards.

'If you conduct the negotiations in a serious, constructive and civilised way there is a lot in common that we can establish.

'I was able to reassure Nissan - and other manufacturers - that that is the way we are going to approach it.'

He finally confirmed he had set out the Government's approach to Brexit in a letter to Nissan chief executive Carlos Ghosn.

He reiterated he did not offer any financial incentives to stay in the UK, acknowledging World Trade Organisation rules barred the Government from offering compensation even if tariffs are imposed.

Mr Clark, 49, said the assurance he gave Nissan included commitments to make funds available for skills and training, to 'bring home' elements of the supply chain which had migrated overseas, to support research and development, and to keep the UK car industry competitive.

'It is simply not possible to compensate for any future risks so the intention of keeping the sector competitive was important,' he said.

'In the motor industry we have a very long track record of investment, in skills in innovations and research and development. But these things are independently reviewed, we can't guarantee them. I hope that they [Nissan] will succeed. They have to apply as companies in the sector have to do.'

Labour's Shadow Brexit Secretary Sir Keir Starmer told ITV's Peston on Sunday show that he will request an emergency debate in the Commons tomorrow on the Government's Nissan deal

Ministers are coming under renewed pressure to explain what assurances were given to the Japanese car giant Nissan

A technician assembles a Nissan car on the production line at Nissan's Sunderland plant in Sunderland, England

But Mr Clark is still under pressure to disclose the terms of any deal struck with Nissan and Labour says it will request an emergency debate in the House of Commons tomorrow to try and force ministers to reveal any guarantees given to the car maker.

Shadow Brexit Secretary Keir Starmer told ITV's Peston on Sunday show: 'There may be a financial element to it - I accept that. They say no money is changing hands.

'I don't know. We need to know and I'm going to try and raise this in Parliament tomorrow because something has been said.

'It's good Nissan are investing, of course it's good, but there are other businesses up and down the country of every size and every sort that need (reassurance).'

He added: 'It's not just this deal that we need to know about - it's what happens to the other businesses.

'Businesses are talking to me all of the time and they are very worried about what happens to them.

'They want to trade on the same terms and if there is a deal that's good enough for Nissan they are saying, and it's quite understandable, 'well, we want broadly the same deal for us'.'

There has been intense speculation as to what the company has been promised after Nissan chief executive Carlos Ghosn announced on Thursday that the 'support and assurances' it had received meant it would build the next generation Qashqai and the new X-Trail models in Sunderland.

The move was hailed by No 10 as a 'vote of confidence' in the UK in the wake of last June's referendum vote to leave the EU, securing 7,000 jobs at the plant and a further 20,000 in the wider economy.

It came after Mr Ghosn met Theresa May in Downing Street earlier this month for talks on the company's future in the UK while Business Secretary Greg Clark has also been out to Japan to meet senior figures at the firm.

However, the Liberal Democrat former business secretary Sir Vince Cable and Conservative ex-business minister Anna Soubry have both said they believed Nissan would not have gone ahead with the investment unless it had been assured the UK would either remain in the customs union or there would be mitigation for any new tariffs it faced.

The Unite trade union said it would be pressing to ensure that whatever assurances had been given to Nissan would apply across the manufacturing sector.

'Our members at car and other manufacturing plants across the country rightly are looking for the same job security that appears to have been secured at Nissan though government intervention and investment guarantees,' said Unite assistant general secretary Tony Burke.

'We need similar arrangement across the manufacturing sector to protect workers and secure these crucial high skill, decently paid jobs.'