SCOTTISH Labour will face a struggle at next year’s Holyrood election after the party’s only MP votes today to pass Boris Johnson’s Brexit deal, according to a leading pollster.

Polling researcher Mark Diffley said the SNP would seize on Ian Murray’s support for the agreement in the months running up to the Scottish Parliament’s poll in May to portray their opponents as a party which backs leaving the European Union.

He added the message of Labour support for Brexit was unlikely to go down well in Murray’s Edinburgh South, which voted by 78% to remain in the 2016 referendum, making it one of the most EU-supporting constituencies in the UK.

While Labour are voting in favour at Westminster, Scottish Labour MSPs are set to reject giving consent to the agreement with only the Tories voting in favour of doing so when Holyrood is recalled today for the debate.

“Ian Murray is in a very difficult situation,” said Diffley.

“UK-wide, the party wants to move on from Brexit. You hear Keir Starmer saying ‘we’re not fighting to remain or go back into the EU’.

“So Ian Murray doesn’t want [to go] against his party but he will have to bear the consequences in terms of his constituency, which is one of the most Remain-supporting in the UK.”

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He added that while the next Westminster election isn’t until 2024, the impact of the Westminster vote would be felt by Labour in the Edinburgh Southern seat at the Holyrood election, which held by Richard Leonard critic, Daniel Johnson who won a month before the EU referendum in 2016 with a majority of 1123.

Diffley said: “It gives the SNP an open goal for the Holyrood election. They can portray whoever is standing as a supporter of Brexit – and whether that's fair or not – it will have some traction in that constituency.

“Public opinion in Scotland is fairly consistently opposed to Brexit since the vote four years ago, about two-thirds of Scots are against it.”

He added: “Clearly the SNP will paint Labour as the midwives of Brexit ... and that they voted the bill through.

“It almost writes the SNP campaign leaflets for them.”

Responding to Diffley’s comments, Catriona MacDonald, the SNP’s candidate for Edinburgh South for the Holyrood election, said: “Ian Murray promised to oppose Brexit. Now he’s backing Boris Johnson’s damaging deal.

“That might make sense to Labour strategists focused on winning back English voters, but it makes no sense to people in Edinburgh Southern.

“He has left Labour in quite a tangle here ahead of next year’s Holyrood elections.

“It’s time we had an MSP who will stand up for our European values and Scotland’s future in the EU.”

Ian Murray and Scottish Labour were approached for comment.