SCOTTISH Labour’s campaign manager has resigned following the party’s disastrous European elections performance.

Neil Findlay announced he will step down as business manager, party liaison and Brexit spokesman – and will leave Holyrood at the 2021 Scottish elections.

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In his resignation letter, he hit out at the "toxic culture of leaks and briefings" and "eternal, internal infighting" within the parliamentary groups in Scotland and Westminster.

However, he said he had made the decision to step down in March following discussions with family, staff and close friends.

He said: “It has been an enormous privilege to serve the Scottish Labour Party, first as a councillor and then a member of the Scottish Parliament.

“I am proud of the work I have done representing my constituents in the Lothian region and of the campaigns I have led in Parliament most notably to retain the Children’s ward at St John’s hospital, supporting the blacklisted construction workers, the mesh campaign, miners’ justice and support for the victims of undercover policing amongst many others.

“I will continue to work hard and diligently on these and other issues right up until I leave parliament.”

In his resignation letter to Scottish Labour leader Richard Leonard, Mr Findlay said: "As you know I have been considering this for the last six months and made my final decision in March following discussions with my family, my staff and close friends.

“We had discussed that I was going to announce these changes at the end of June but, with the European elections complete, now seems like a more appropriate time.”

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He said he had spent 18 years as a politicians and it was now time "for a new generation of socialists to come through".

Mr Findlay also outlined a series of measures to rebuild the Scottish Labour Party, including having a "clear and easily understood position on the constitution".

He called for an "end to the eternal, internal fighting within our party and the toxis culture of leaks and briefings that come from some within the Scottish and UK parliamentary groups".

He added: "This self-inflicted harm has to stop - our party members and our leadership teams deserve so much better.

"Scottish Labour will win again when the focus in on the public not the internal politics of the parliamentary group."

He later added on Twitter: "Life is too short to be involved in endless internal battles with people who are supposed to be on the same side."

Mr Findlay's resignation comes after Labour plummeted to fifth place in the European elections over the weekend.

The disastrous result has sparked what one source called an "existential" crisis in the party, and Mr Findlay was under fire over his role as campaigns chief.

The Lothian MSP is seen as a key ally of Mr Leonard and UK Labour leader Jeremy Corbyn.

His resignation so soon after the result will be seen as an attempt to deflect criticism from Mr Leonard, who has faced calls to quit.

Mr Leonard said: “I am very sorry that you will not be able to be a member of the Scottish Labour front bench but I also know from our conversations that this is the right decision for you personally and in that you have my full support.

“Your service as an MSP has been outstanding. You have served the communities you represent with dedication and on the basis of your strongly-held principles.

"Your campaigns, such as the mesh campaign, the pressure for an inquiry into the policing of the miners’ strike, and blacklisted construction workers are a model of what being a member of this Parliament should be about.

"Through this work you have demonstrated the important lesson that for socialists the purpose of the Parliament is not to be found in the daily grind of procedural arguments, but instead in how the Parliament relates to the lives of working class people in this country."