A war of words has broken out between UK and Scottish Government ministers after David Mundell, the Scottish Secretary, said Edinburgh had made a “significant move” over Brexit and was now calling for full access to the European single market rather than full membership of it.

However, following a meeting of the Joint Ministerial Committee at Westminster, Michael Russell, the Scottish Government minister for UK Negotiations on Scotland's Place in Europe, was adamant that there had been no shift whatsoever.

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He explained what the SNP administration wanted was the Norway option ie respecting the so-called “four freedoms” of the EU over movement of goods, people, services and capital but not having direct decision-making powers within the single market.

In an extraordinary scene outside Commons committee room 16, where the JMC had taken place, Mr Mundell and Mr Russell engaged in a joint press briefing but expressed totally opposite views as to the position of the Scottish Government.

The Scottish Secretary said there had been “clarification” from the SNP administration. “Their priority is access to the single market. There has been a lot of confusion in recent weeks about what membership meant compared to access. Mike, from my perspective, has clarified that and that’s a positive because we are much more on the same page.”

But Mr Russell disagreed and interjected to deny Mr Mundell’s assertion that the SNP leadership had made a significant shift.

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He explained: “I want to have an arrangement within the single market that allows us as close as what we have at the moment.” He referred to the Welsh Government’s phrase ‘full and unfettered access,’ noting: “We are in the process of trying to define what it means.”

The minister stressed that the key issue for the Scottish Government was how it could continue to observe the four freedoms like the Norwegians. “That’s the next best, we would describe that as EEA/EFTA membership. I’m not talking about an arrangement outside the single market.”

But Mr Mundell argued that when people referred to ‘membership’ they meant continuing to be a member of the EU. “The UK is not going to be a member of the EU because we are leaving and Scotland as part of the UK will be leaving the EU. So it is about access and the form of access.”

“Not outside the single market; that’s the key point,” declared Mr Russell.

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He explained that Norway, Iceland and Switzerland were “members in that way” but what they lacked was a decision-making role.

When it was put to Mr Russell, that this was not real membership, he disagreed, saying: “Norway would describe it as membership but not participation in the decision-making process.”

Mr Mundell said the important thing was the two governments were now in a debate about negotiating access with the single market and not in a “futile” one about membership.

But Mr Russell declared: “I disagree.” He then said he wanted to respect the wishes of the Scottish people, who wished to retain “the maximum[access] they can but not outside the single market”.

“There we are,” insisted the Scottish Secretary, “maximum access; it’s a negotiation about access to the single market.”

He added: “I don’t think anybody could suggest, given the language that the Scottish Government has previously used, that this does not represent a big change in their public position. And it’s a helpful one.”

Earlier, Mr Russell told the Commons Scottish Affairs Committee that if Scotland did not get a “differentiated option” from the rest of the UK on Brexit, then its position would be “impossible”.

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Professor Anton Muscatelli, who heads the panel advising Nicola Sturgeon on Brexit, told MPs how maintaining freedom of movement was “absolutely critical” to continue the flow of skills to allow Scotland to grow.

The Scottish Government options paper – expected to be published next week - will be discussed at the next JMC meeting in January and before the key plenary session takes place involving the Prime Minister and the First Minister.