Royal Mail has won its legal battle to prevent a postal strike after the High Court backed its application for an injunction.
The decision averts the possibility of strikes in the run-up to the general election and Christmas.
Last month, 100,000 Royal Mail staff were balloted and voted to take action over job security and terms.
But Royal Mail argued that the ballot had “potential irregularities” and was null and void.
The Communications Workers Union (CWU) responded to the decision in a tweet: “The High Court has ruled against us. Genuinely this is an utter outrage. 110,000 workers vs the establishment.”
Members of the CWU voted by 97% in favour of a nationwide strike, saying the company had failed to adhere to an employment deal agreed last year.
Royal Mail denied this and said it had evidence of CWU members coming under pressure to vote “yes” in the ballot.
This included, the company said, union members “being encouraged to open their ballot papers on site, mark them as ‘yes’, with their colleagues present and filming or photographing them doing so, before posting their ballots together at their workplace postboxes”.
Royal Mail said this amounted to a “de facto workplace ballot”, contrary to rules on industrial action, to maximise the turnout and the “yes” vote.
Royal Mail’s procedures state that employees cannot open their mail at delivery offices without the prior authorisation of their manager.
But CWU lawyers argued there was no evidence of interference with the ballot and that “legitimate partisan campaigning” by the union in favour of a “yes” vote did not violate the rules.