UPDATED 12.14pm: The sun is out and planes are starting to take off again from Christchurch International Airport.

Thick fog had grounded all Jetstar and Air New Zealand domestic flights, along with a number of international ones.

NZME reporter Grant Bradley was one of those affected by the delays, and says passengers' attitudes have notably changed in the last hour.

"They're moving planes, they're looking a bit cheerier but there was an air of resignation earlier in the morning, when people weren't going anywhere. They were packing out cafes, contacting friends and family."

One of the hundreds affected Kasey Miles, said she was meant to fly to Auckland at 8 o'clock this morning, but cancellations have meant she's missed her connection to Bali.

She said most people at the airport are remaining calm, despite their frustrations.

Ms Miles said Air New Zealand is hoping to be airborne soon.

"Not really sure what's going on at the moment, but hopefully 11 oclock is the next time flights will start leaving."