LEN McCluskey’s acknowledgement that Scottish Labour will “wither on the vine” unless they back indyref2 highlights the party’s “rapid slide into irrelevance”, a senior SNP figure has said.

Former Unite the Union chairman McCluskey, who continues to be a Labour member despite his public issues with current leader Keir Starmer, told Novara Media's Tysky Sour podcast that the constitution is Scottish Labour’s big problem.

Speaking to The National, the SNP’s Scotland spokesperson Mhairi Black welcomed the trade unionist’s comments.

Black, who was one of several SNP MPs to win their seat from Labour in 2015, said: “Scottish Labour’s rapid slide into irrelevance in Scotland will continue as long as they keep supporting Westminster control in Scotland – and Len McCluskey’s remarks underline that yet again.”

The National:

Len McCluskey speaking to Aaron Bastani

The Paisley and Renfrewshire South MP also criticised Scottish Labour leader Anas Sarwar for standing with Westminster in “denying the people of Scotland the democratic choice of a referendum”.

McCluskey has told Sarwar on multiple occasions “to wake up and smell the coffee” and support a new referendum or risk losing “another generation” in Scotland.

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Despite this, the Scottish Labour chief has said that the party does not “believe in” independence and councillors must show support for the Union during this year’s council elections.

Black went on: "On May 5, people in Scotland can send a message to reject the broken Westminster system and prioritise action to tackle the cost of living by voting SNP in the local elections."

The National:

McCluskey has been a long-time Labour member and donor who strongly supported Jeremy Corbyn during his time as Labour leader.

While he led the party, Corbyn’s independence policy stated that he wouldn’t grant a referendum in the early years of a Labour government.

However after he left the position, Corbyn conceded that a second referendum would occur “within a few years” and added that he was “strongly in support of people having their voice”.

Since the 2010s, Scottish Labour has had a steady decline in Scotland - losing seats in every in every Scottish Parliament election including 40 seats in Westminster following the 2014 referendum.

The National has reached out to Scottish Labour for a comment.