Jim Murphy will be stepping down from his post as Scottish Labour leader following his ousting as an MP and Labour’s huge losses to the Scottish National Party (SNP) in the general election.

He said he would step down at a meeting of the national executive in Glasgow next month, when he submits wide-ranging plans to reform the beleaguered party.

Mr Murphy faced repeated calls to resign last week after his party lost 40 seats in Scotland, being wiped out by the SNP in all but one solitary seat.

He won a vote of confidence by the Scottish Labour executive today and said he will use the mandate to put forward a report on how to rebuild the party and win back votes.

“This was a terrible election defeat both north and south of the border - I’m under no illusion about how big our defeat was or how big our challenges are,” he said.

“We need a plan to build on the residual strength and support we got from hundreds of thousands of Scots at the general election.”

Mr Murphy said his key recommendation was a “one member, one vote” policy for leadership elections.

He wants a successor in place by the summer to campaign for next year’s Scottish Parliament elections and said he will not be standing as an MSP.

The former East Renfrewshire MP described the Labour Party as a “second family” where he had “laughed and cried, won and lost” among some of his best friends.

Mr Murphy said he felt great pride at having worked for a “great cause…for the betterment of people whose names you don’t know and whose faces you will never look upon”.

He added: “Scotland needs a strong Labour Party, Scotland needs a united Labour Party.

“We have been the greatest force for change in our nation’s remarkable history.

“The Scottish Labour Party will rise again, it will be under someone else’s leadership, and I’m confident about my party’s future.”

Unite general secretary Len McCluskey had called for Mr Murphy to resign (Getty)

Mr Murphy used his resignation speech to launch an attack on Len McCluskey, the General Secretary of Unite.

He claimed he had been at the centre of a “grossly insulting” campaign by the union to blame Scottish Labour for the party’s UK-wide general election defeat.

“One of the things about stepping down is that you can say things in public that so many people in the Labour Party can only say in private,” he continued.

“The leader of the Scottish Labour Party doesn’t serve at the grace of Len McCluskey and the next leader of the UK Labour Party should not be picked by Len McCluskey.”

The major political figures who lost out in the General Election Show all 16 1 /16 The major political figures who lost out in the General Election The major political figures who lost out in the General Election Ed Balls Ed Balls lost his seat in what was the biggest shock of an extraordinary night of election results. His defeat in compounded Labour's woes in a dismal night, which saw the party lose all but one of its Scottish MPs and will undoubtedly lead to Ed Miliband standing down. The major political figures who lost out in the General Election Nigel Farage OK, so he came close to being upstaged by a professional comedian – Al Murray aka the Pub Landlord, had also lost in South Thanet. But as he lost his fight to become an MP and resigned his Ukip leadership, Nigel Farage did manage to get in a few gags. He began by railing against the editors of the The Sun and the Daily Mail, sarcastically calling them “geniuses”. But perhaps bearing the last election in mind, when he was in intensive care following an air crash, he said after the result that he felt “pretty good”. “Never felt happier,” in fact. A weight lifted off the old shoulders. Quite right too, old boy. More time for the saloon bar and a pint, or five. AFP/Getty Images The major political figures who lost out in the General Election Vince Cable A huge scalp for the Conservatives, even though he was part of their coalition government. The Liberal Democrat Business Secretary lost his Twickenham seat to Tory candidate Tania Mathias. Cable had held the seat since 1997 and was a strong figure in the Lib Dems, having previously been deputy leader. Christopher Furlong | Getty Images The major political figures who lost out in the General Election Jim Murphy A sign of how dire things are in Scotland now for the Labour party. The leader of the Scottish Labour Party, Jim Murphy, lost his Renfrewshire East to the SNP, having held the seat since 2005. He held a number of cabinet positions under the administrations of Tony Blair and Gordon Brown. Jeff J Mitchell | Getty Images The major political figures who lost out in the General Election Danny Alexander The Chief Secretary to the Treasury and Nick Clegg's right-hand man, Danny Alexander, lost his seat of Inverness, Nairn, Badenoch and Strathspey to the SNP. His aides admitted defeat several hours before the formal decision was due. There were suggestions that the SNP vote could be as high as 50 per cent. BEN STANSALL | AFP | Getty Images The major political figures who lost out in the General Election Esther McVey The Minister of State for Employment and one of the few women in David Cameron’s male-dominate cabinet, Esther McVey had only held Wirral West since 2010. Her 2,436 majority was overturned and Labour's Margaret Greenwood won the seat with a 417 majority. BEN STANSALL | AFP | Getty Images The major political figures who lost out in the General Election George Galloway The former Labour MP had held the seat of Bradford West since 2012 for the Respect Party. He previously held the constituency of Bethnal Green and Bow for Respect between 2005 and 2010, although he unsuccessfully contested Poplar and Limehouse in 2010. Nigel Roddis | Getty Images The major political figures who lost out in the General Election Charles Kennedy Another huge Lib Dem scalp, with the SNP taking the seat of Ross, Skye and Lochaber from the former leader of the party. Kennedy had led the Lib Dems between 1999 and 2006 and had become something of an elder statesman of the party. He conceded defeat ahead of the official declaration and said he would not give any TV interviews. He had been an MP since 1983. Jeff J Mitchell | Getty Images The major political figures who lost out in the General Election Douglas Alexander The shadow Foreign Secretary and Ed Miliband's Chair of General Election Strategy, Danny Alexander had been the MP for Paisley and Renfrewshire South since 1997. He lost his seat to the SNP, with the party now holding a 9,076 majority. Labour's share of the vote was down by 21.3 per cent. Jeff J Mitchell | Getty Images The major political figures who lost out in the General Election Simon Hughes Simon Hughes held a key Liberal Democrat seat in London, Bermondsey and Old Southwark, which he held from 1983. Hughes is a former deputy leader of the Lib Dems and had been minister of state at the Ministry of Justice since 2013. He was previously the President of the party, as well as a two-time leadership candidate, and stood for the party in the 2004 Mayoral election. Rob Stothard | Getty Images The major political figures who lost out in the General Election Mark Reckless An MP for Rochester and Strood since 2010, Reckless switched from the Conservatives to Ukip in September 2014 and winning the seat outright in November. He was the second Ukip MP after Douglas Carswell, and his loss is a huge blow to Nigel Farage’s party. Carl Court | Getty Images The major political figures who lost out in the General Election Margaret Curran Margaret Curran had held Glasgow East since 2010 and was the shadow Secretary of State for Scotland. She had previously been the MSP for Glasgow Baillieston (a seat she might wish she still held, as it is still held by Labour under the title Glasgow Provan). Jeff J Mitchell | Getty Images The major political figures who lost out in the General Election David Laws A Liberal Democrat MP for Yeovil since 2001, he was the minister of state for Schools. He had briefly been Chief Secretary to the Treasury after the 2010 election, only holding the office for 17 days after resigning due to the disclosure of his Parliamentary expenses claims. Laws was a key negotiator for the Lib Dems when the coalition was being formed five years ago. Jeff J Mitchell | Getty Images The major political figures who lost out in the General Election Jo Swinson On her election in 2005, she was the youngest member of the House of Commons. Under the Coalition government, the Lib Dem MP was the Under-Secretary of State for Employment Relations, Consumer and Postal Affairs and for Women and Equalities. She lost her seat of East Dunbartonshire to the SNP's John Nicholson. Matthew Lloyd | Getty Images The major political figures who lost out in the General Election Ed Davey The Liberal Democrat Energy and Climate Change Secretary Ed Davey had been the MP for Kingston and Surbiton since 1997. Davey championed the Lib Dems' role in ensuring the Conservative-led Coalition championed the green agenda. However, the well-known Lib Dem MP lost his seat to the Tories, having held the seat in 2010 by 7,560 votes. Jeff J Mitchell | Getty Images The major political figures who lost out in the General Election Lynne Featherstone Lynne Featherstone lost her London seat of Hornsey and Wood Green to the Labour party. She was a former junior Home Office minister with responsibility for equality, then becoming junior minister with responsibility for international development. Dan Kitwood | Getty Images

The Unite leader had been one of several voices calling for Mr Murphy to step down questioning Scottish Labour’s election strategy.

Kezia Dugdale, Mr Murphy’s deputy, will be acting leader of the Scottish Labour Party until a successor is appointed.

Nicola Sturgeon, the Scottish First Minister and leader of the SNP, reacted to the resignation on Twitter.

She said: “I wish Jim Murphy all the very best for the future. Leadership is not easy and he deserves credit for standing up for what he believes in.”