The Prime Minister today praised the fire and emergency services battling the fire that ripped through the SkyCity Convention Centre, saying now "the plan has to be to restore it".
She also made assurances APEC 2021 would still be held in New Zealand.
"We are in a much better space than this morning and I expect we will see a much bigger difference tomorrow again, there's no doubt it’s had a significant effect on the activity in the CBD," Jacinda Ardern said.
"Our advice is for employees to stay in touch with their employers, it will be case-by-case."
Fire and Emergency NZ have said the fire has been contained after breaking out yesterday afternoon - but the worst was not yet over.
Talking to media from Auckland, Ms Ardern said the extent of damage would not be known "for some time".
"(The convention centre) had come so far and to now see this major, major set back will be a real blow to this work force," she said.
"But I know they will be committed as everyone here to seeing that restored.
"You can see from the outside it’s got the potential to be a beautiful building, it’s unique, the glass paneling some might say holding up against some pretty high pressure water hoses.
"Now the plan has to be to restore it."
This morning, Auckland Mayor Phil Goff told TVNZ1's Breakfast a 'Plan B' location to host the 2021 Asia-Pacific Economic Cooperation (APEC) was being investigated.
APEC draws world leaders, business leaders and international media, estimated to bring 10,000 people to New Zealand.
Ms Ardern said it would still be held in Auckland, but was unsure where exactly it would be hosted.
"The question of APEC in 2021 is not in question," she said.
"We have contingency, we are ready to trigger it if required."