Mr Miles said he had broad support, and was likely to win the union’s nomination.
However, before the political committee could vote they were told of a ‘new rule’ that meant that he was ineligible to be a candidate. Only one candidate was therefore allowed to go forward for nomination.
Mr Miles’ political team say this new rule still hasn’t been shared with them by Unite, that it hasn’t been published and it hasn’t been applied before. They add that there is no evidence that the drafting of such a rule even covers Labour party leadership elections.
Mr Miles said he was not informed before, during or after about any alleged issues with his eligibility.
He added that requests to Unite for fairness and common sense have been rebuffed. He says his campaign’s letter to General Secretary Sharon Graham hasn’t been answered.
A senior official of the Unite has told Mr Miles they stand by their decision.
In a statement, Mr Miles said: “I participated in the Unite the Union nomination hustings for the Welsh Labour Leadership on 16 January. Both candidates for the leadership spoke and answered questions.
“During the discussion held after the hustings by the political committee to nominate their preferred candidate, I understand they were told for the first time that I was ineligible to be nominated by the union due to a new rule that no one was aware of, had not been published and which hadn’t been applied previously. The political committee was then prevented from voting to express a view on the candidates, in light of this new rule.
“This new rule was not declared when I was invited by Unite to attend and participate in the nomination hustings. Neither was it referred to during the hustings. After the hustings concluded, the leadership of Unite failed to mention it to me. To date, I have not seen any evidence the rule even exists for the purpose claimed.
“Members will rightly expect that rules to nominate a candidate for the next leader of our party and our government should be transparent and be applied fairly.
“A longstanding trade unionist has said to me: if this can happen to a candidate for Welsh Labour leader, and First Minister of Wales, how will lay members wishing to progress in the union be treated? This is a fair question. “
Mr Miles added: “The support I’ve gained in this contest is based on hard work in the Senedd and with local government since I was first elected in 2016. There are those who may feel others are more entitled to support because they have been around longer. Everyone is entitled to their view. But the way to express their view is through the proper democratic process.
“I’m standing to lead an inclusive government in a nation where opportunities are open to everyone. I have an ambitious programme that includes defending and extending workers’ rights, and the urgent fight to protect high quality jobs – things that the majority of Unite members and officials stand for.
“I did not want to make a statement like this, but so many union members have made it clear publicly that they are deeply unhappy with the way the nomination has been made. I am standing up for the principle of fairness and equal treatment, as any good trade unionist would.
Mr Miles thanked “the whistleblowers at all levels in Unite who have made sure this stitch up was not kept secret”.
What is the rule? I keep looking for it but cannot see where it is, only that it is a secret.