The Ports of Auckland says it is too late for the Auckland mayor to be offering to mediate in the company's dispute with the Maritime Union.
Len Brown has offered to do what he can to help resolve the long running wrangle over a new collective contract.
The port has made 300 watersiders redundant following eight months of talks aimed at resolving a dispute over a collective contract.
The Maritime Union has appealed to Len Brown to intervene to save jobs.
Ports of Auckland is owned by the Auckland Council, via its wholly-owned subsidiary, Auckland Council Investments Limited, and Len Brown has said he is constrained by law from any hands-on role.
He told TVNZ's Q+A programme on Sunday he can't run the port out of his office, but he is prepared to sit with both parties in a mediated process if they will agree to meet.
The Maritime Union has welcomed the offer, saying it will meet any time, any day with any decent offer to settle the dispute.
But Ports of Auckland chairperson Richard Pearson says it is too late for that.
He says the decision to outsource the stevedoring contractors has already been made and implemented.
"They are already appointed and we cannot go back on that, that is irrevocable", he says.
Mr Pearson says he would like the mayor instead to persuade the workers to apply for the new roles.
Company says stevedores earn $91,000 on average
Ports of Auckland has laid bare its negotiations with the Maritime Union in a full-page advert in a Sunday newspaper, but denies it is engaging in a public relations war.
The advert is the third from the company since Wednesday when it announced it will introduce competitive stevedoring into its Fergusson and Bledisloe Container Terminal operations. Up to 292 employees, mainly stevedores, will be made redundant.
Members of the Maritime Union are halfway through a four-week strike over the decision to contract out the work.
In an open letter addressed to Aucklanders, the company cites an independent report which shows the stevedores at the port have been on average salary packages of $91,000 a year.
The advert goes on to claim that the stevedores work just 26 hours for every 40 hours of pay.
Maritime Union president Garry Parsloe says the company is trying to win public support - which he believes is firmly in favour of the workers.
But Mr Pearson says the adverts have got nothing to do with opinion polls and everything to do with telling the facts.
"They need to know that the board has confidence in the management and in particular (chief executive) Tony Gibson, who's done a fantastic job.
"We are fully supportive of all the changes he wants to put in place in that company and he's exactly the right guy to be doing it."
Mr Pearson says he does not know how much the adverts cost.