Salvage work on the stricken cargo ship Rena has been suspended following forecast bad weather this week.
The ship has been grounded on Astrolabe Reef off the coast of Tauranga since 5 October last year.
Maritime New Zealand says it is in a fragile state and a storm is expected to cause swells of up to eight metres from Tuesday.
It says the Smit Borneo barge and its crew have returned to port and are likely to stay there for the rest of the week.
Bad weather could further damage the ship and cause the loss of more containers. So far, 685 have been salvaged.