A failure to sort out disagreements between London and Edinburgh on Theresa May’s flagship EU Withdrawal Bill would lead to “trench warfare,” Michael Russell, the Scottish Government’s Brexit minister, has warned.

Nicola Sturgeon’s administration believes the legislation is a “power-grab” by Whitehall, insisting, post withdrawal, powers should go straight from Brussels to Holyrood.

The UK Government argues that the powers need to go to Westminster first before being passed to Edinburgh to ensure the integrity of the country’s single market is maintained.

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Appearing before the Commons Scottish Affairs Committee, Mr Russells told MPs there should be no imposition from Whitehall but full consent by Holyrood with co-decision-making on post-Brexit frameworks.

Asked by Labour’s Danielle Rowley what would happen if MSPs continued to withhold consent, he said the UK constitution would then be put in a unique circumstance, creating a “real great difficulty” between the governments and the parliaments.

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While he noted how getting agreement on the Withdrawal Bill would help smooth the way for consent on subsequent Brexit bills, the minister warned that failure to do so “would frankly start a process which would become more difficult with every single following day…a kind of trench warfare and that’s in nobody’s interest.”