But other fertilisers including urea flow freely, said Sean Mackle of industry lobby Fertilizers Europe, adding that the patchy approach weighed on implementation.

Speaking following the meeting on Tuesday night, Sinn Féin councillor Liam Mackle said the majority of councillors had supported the deal which will "hopefully bring an end to industrial action".

But Craig Mackle, the mayor of Kaikōura, told reporters he believed the boat had hit a surfacing whale.

Mr Mackle said conditions in the bay at the time were "perfect" and that officials assumed the whale had surfaced beneath the vessel, causing it to overturn.

Mr Mackle told the Associated Press that such accidents are unheard of in the region, but the number of whales in the area in recent days had caused him to worry about a collision.