At least six more ships are expected to shun Auckland before Sunday as the country's largest container port lies crippled from the early days of a three-week strike.
That is on top of 12 ships already diverted to other ports during seven strikes against the council-owned port company since early December, when about 300 workers were also locked out for 48 hours.
Many other ships have been delayed and the company estimates its revenue loss so far from the diversions at up to $3.5 million, not counting hefty costs to importers and exporters unable to get goods to market in time.
The dispute has also started putting a squeeze on exports from other ports, which rely on the supplies of empty containers imported through Auckland.
Although shipping giant Maersk hopes to berth a vessel in Auckland, and have it worked by non-striking port staff, the Maritime Union says it will believe that when it happens.