Hundreds of people have begun arriving on the West Coast from around the country for a memorial service for the workers who died in the Pike River Coal mine disaster.
The company is still battling to put out a coal fire inside the mine where the bodies of the 29 men are entombed.
A remembrance ceremony will be held at the Omoto racecourse, near Greymouth, on Thursday. Thousands are expected to attend.
Hokitika Airport has been given a special exemption until Sunday to take larger aircraft, but thick sea fog rolling in from the Tasman prevented flights landing on Wednesday morning.
Some passengers were travelling by bus from Christchurch instead.
Prime Minister John Key is is calling on all New Zealanders to observe a two-minute silence at 2pm, the time the service is due to start.
Mr Key says the tragedy has affected all New Zealanders.
The workers died in explosions at the mine which began on 19 November.