Unite the Union are calling on the operator of Port of Liverpool to be 'truthful' about the pay rise they are offering employees.
It comes after Peel Ports wrote to the bosses of Unite urging them to call off their latest round of strike action.
Peel Ports say Unite have "organised mass meetings to carry out show-of-hands votes involving less than 25% of the workforce" and would like employees to have a "confidential and democratic" vote.
The company say a secret ballot will allow them to gauge individual responses to the company's final pay offer of 10.2%.
Peel Ports chief operating officer David Huck said: “We have made Unite the Union a very generous and realistic final offer of 10.2% but they have so far refused to allow staff to vote on it via an independent postal ballot."
He added: “A significant number of employees have raised concerns with us about the recent ballot process.
"We have therefore written to Unite leaders today asking them to give their members a proper vote, rather than simply relying on a show-of-hands in mass meetings involving only a small minority of employees."
The company said their latest offer is double their original pay increase and it is "2% higher than other port operators in the UK".
Mr Huck said: “The Union’s demand, for almost 16%, is completely unrealistic, but they have refused to enter arbitration with ACAS or even to put our 10.2% offer to their membersin an independent and formal process.”
In response, Unite national officer Robert Morton said: "Peel Ports is fudging the numbers.
"The 10.2% figure is based on the maximum someone could earn if they work overtime on top of their weekly contracted hours.
"If the company offered a clear 10.2% rise for all grades we would take it to ballot.
"The reality is that the company has offered our members around 8.3% - some pay grades would receive less than that and others slightly more.
"Our members have already overwhelmingly rejected this offer, which is nowhere near the RPI inflation rate of 12.3%, during a vote in a mass meeting.
"As with Peel's redundancy threats, this is another transparent attempt to break the strike.
"It won't work: Both our members and Unite are resolute – Peel Ports brings in huge profits and needs to put forward a pay rise that reflects soaring inflation.
"Unite would be happy to attend Acas, but the company has told us it will not budge on the 8.3% offer.
"There is no point conducting talks until the company agrees to negotiate on its position, which means being truthful about what it is actually offering."
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