Nicola Sturgeon has insisted Scottish Secretary David Mundell must resign by the end of the day if he is to retain “any last remaining scrap of principle or credibility”.

The First Minister made the comment after negotiators in Brussels agreed a text for the proposed political declaration on the future relationship between the European Union and the UK.

She said the agreement’s insistence that the two parties “should cooperate on inter alia access to waters and quota shares" represented a betrayal of previous Tory pledges on fishing.

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Last week, all 13 Scottish Tory MPs – including Mr Mundell – signed a letter to Theresa May stating: “We must be able to negotiate access and quota shares with the EU and other third countries independently on an annual basis, without any pre-existing arrangements being in force.

“This means that access and quota shares cannot be included in the Future Economic Partnership, allowing the UK to become an independent coastal state both in principal and in practice.”

The Herald:

Speaking during First Minister’s Question, Ms Sturgeon said this was directly contradicted by the statement in the agreement.

She said: “The political declaration that has been agreed between the UK Government and the European Commission this morning represents another Tory sell-out for Scottish fishermen.

“What we see is that the Scottish fishing industry will be used as a bargaining chip in wider trade talks.”

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Ms Sturgeon said the political declaration made no mention of annual negotiations, “which I happen to know the UK Government was trying to secure and they failed”.

She added: “So in terms of David Mundell’s position, I would simply say this: his position is a matter for him.

“But if David Mundell is still in office by the end of today in light of this political declaration, he will have forfeited forever any last remaining scrap of principle or credibility that he had.”

Her spokesman later accused the Scottish Tories of a “mammoth, epic sell-out”.

It comes after European Council president Donald Tusk announced the text had been agreed in draft form by EU and UK negotiators and "agreed in principle at political level".

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The move clears the way for a special Brexit summit to go ahead in Brussels on Sunday, when leaders of the 27 remaining EU states are expected to give their stamp of approval to the declaration alongside the 585-page withdrawal agreement setting out the terms of the UK's departure.

Mr Mundell said he would take no lessons on standing up for fishermen from Ms Sturgeon, insisting she is committed to trapping them in the hated Common Fisheries Policy (CFP).

He said the declaration gives the UK power to “assert its position as an independent costal state with practical sovereignty over our waters”.

Responding on Twitter, he added: “We will negotiate and decide, as an independent coastal state, on access and quota on an annual basis just like Norway and Iceland do now.

“The surest way to guarantee the EU access to Scottish waters would be to rejoin the CFP - exactly what @NicolaSturgeon is demanding.”