JIM Murphy is today facing the battle of his political life with Scottish Labour's governing body set to consider a vote of no confidence in his leadership.

Labour's Scottish Executive Committee, made up of 31 parliamentarians and representatives of local parties, trade unions and other affiliated bodies, will meet in Glasgow for the first time since a catastrophic defeat at last week's general election, with the party retaining just one of 41 seats north of the border.

The Communication Workers Union (CWU) yesterday ramped up pressure on Mr Murphy, who lost his own East Renfrewshire seat, when it added its name to a growing list of organisations which have called for his head.

A large block of Labour MSPs are also known to be deeply unhappy with Mr Murphy remaining as leader, with more than 12 holding an unofficial meeting on Thursday in an attempted coup.

A spokesman for the union, which is affiliated to the Labour Party and represents workers in post, telecoms, mobile, and financial services companies, said: "CWU is calling for the resignation of Jim Murphy as Scottish Labour leader following the party's performance in the general election, which was particularly disastrous in Scotland.

"It is clear that the Labour Party needs to rebuild in Scotland and CWU believes that will be done most effectively under new leadership."

The CWU call for Mr Murphy to go follows Len McCluskey, the boss of Britain's largest trade union Unite, urging him to resign after blaming him for Labour's defeat UK-wide.

The Unison trade union, also affiliated to Labour, has said that it is "unprecedented for a party leader not to stand down after such a defeat".

While they stopped short of calling for him to resign, they said if there was a wider call for a new leader in the party, they would not oppose it.

Leaders of the trade union Usdaw offered their support to Mr Murphy, saying a second leadership contest in a year in the party in Scotland would be "navel-gazing". The Community trade union, which represents workers across all sectors, has also offered its backing to Mr Murphy.

Mr Murphy faces another challenge to win over the grassroots of the party. The first meeting of any Constituency Labour Party (CLP) since the election defeat saw a vote of no confidence passed in Mr Murphy's leadership by 18 votes to 10.

However, it is understood following the meeting, the Almond Valley CLP attempted to submit their resolution to the Scottish Labour Party but it was rejected on the grounds that 25 per cent of the membership had not been present.

Sources within the group accused Scottish Labour HQ of attempting to silence the grassroots of the party, claiming it had never before seen decisions rejected on the same grounds. Midlothian CLP is also likely to vote on a no confidence resolution when it meets next week.

Left-wing Scottish Labour activists have already urged Mr Murphy to resign to allow the party to reconnect with the public without the distraction of a rejected MP at the helm.

A meeting of about 100 activists organised by the Campaign For Socialism reached the almost unanimous decision that "Jim Murphy must go" on Wednesday.

Neil Findlay, the left winger who stood against Mr Murphy in his leadership bid last year, quit the Scottish Labour shadow cabinet last weekend while Alex Rowley later resigned as the party's local government spokesman and called on his boss to quit. Elaine Smith, Labour MSP and deputy presiding officer, has also called for his resignation.

Sources associated with the plot to oust Mr Murphy said last night that while he may survive today's vote, his bid to remain Scottish Labour leader would be mortally wounded.

However, he won backing from Edinburgh South MP and shadow Scottish Secretary Ian Murray, who is the party's only remaining Scottish member of parliament.

Mr Murray said: "With just a year until the Scottish Parliament elections this is not the time for division. We need to rebuild our movement together with Jim Murphy as our leader, so that the people of Scotland will place their trust in our party again.

"Families across Scotland are hurting because of unfair Tory austerity and need a strong Labour voice standing up for them. Instead of spending so much time talking about ourselves we need to focus on Scotland and the change this country needs."