Radio New Zealand understands a ship being detained at the Port of Napier became involved in a dispute after carrying cargo from Iran to India, where it was rejected as sub-standard.
The registrar of the High Court in Auckland ordered the arrest of the Sheng Mu under the Admiralty Act 1973, at the request of United Arab Emirates shipping company Golden Waves FZC.
The Sheng Mu is currently carrying fertiliser. The ship's managers, Fenwick Shipping Services of Hong Kong, says the dispute is between Tradelines LLC of Dubai and Golden Waves FZC over a previous shipment.
The disagreement began when a buyer refused to take delivery of a shipment of coking coal from Iran at an Indian port, saying it was of poor quality.
However, a source who does not wish to be named, told Radio New Zealand the ship's current journey to Napier, where it was seized, is completely unrelated to the shipment several months ago.
They say the ship is entangled as a third party in the dispute because the law dictates that the vessel remains connected to its previous shipments.
Fenwick Shipping says the ship's detention in Napier is unwarranted and is urging those involved to settle their dispute quickly.
Port of Napier chief operating officer Chris Bain says the port is full and it has been a juggling act trying to find a berth for it.
Mr Bain said it was not clear how long the ship would be required to remain there. The crew are not allowed to leave the vessel.