Gerard Coyne, who has lost his bid to become general-secretary of Unite, has insisted Len McCluskey's narrow victory in the union's leaderhip election was "no vote of confidence".
In a damning indictment of the democratic process within Britain's biggest union - which saw Mr McCluskey re-elected as general secretary on a turn out of just 12 per cent and a winning margin of 5,000 votes - Mr Coyne said the election result "sends some very serious messages to Unite".
Speaking after the left-winger's victory was announced on Friday afternoon, Mr Coyne said: "I am proud to have run a campaign that faced up to the issues that concerned members.
"Unite needs to change, and it needs to put its focus back where it belongs: on looking after the real interests of the members of the union.
"It's been a hard and robust campaign.
"The union machine consistently attempted to bully and intimidate me, something that has continued even after the close of polls.
"Nevertheless tens of thousands of members backed my fight to change our union for the better.
"On the downside, turnout has fallen disastrously. Many members have reported to me that they did not get their ballot paper at all or if they did, that it arrived literally on the day polls closed and so was useless.
"This was no vote of confidence, with falling turnout and a halving of Len McCluskey's previous vote. It's time for all those that were involved to reflect on the message that the union's membership are sending to the organisation."
During his campaign, Mr Coyne gave an interview to the JC in which he called for Jews to rejoin the union should he beat Mr McCluskey.
He also said three senior members of Unite, with close links to Mr McCluskey and Mr Corbyn, had chosen to “defend the indefensible” when they backed two individuals at the centre of an antisemitism enquiry at Oxford University’s Labour Club.
Mr Coyne also insisted that under Mr McCluskey’s hard-left leadership the union had wrongly “singled out” the Israeli-Palestinian conflict when “for many of our members it is not something at the forefront of their minds”.
Following the interview, Mr Coyne called in police over a possible hate crime after he was subjected to antisemitic abuse on social media.
Mr Coyne was suspended from his post as Unite’s West Midlands regional secretary pending an investigation yesterday, only 24 hours before the election result was revealed.
He is facing claims that he brought the union into disrepute during the campaign.
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