Air travel disruption will continue into Thursday, with airlines cancelling more flights because of volcanic ash from an eruption in Chile.
The ash cloud is lingering at about 20 thousand feet and extends from New Zealand to the eastern seaboard of Australia.
The Civil Aviation Authority (CAA) said on Wednesday that it expects the ash cloud to linger over New Zealand airspace for about another two days.
The Puyehue volcano in Chile began erupting on 4 June and is causing disruption for thousands more passengers as the ash cloud circles the southern hemisphere for the second time.
Jetstar and Qantas have cancelled all trans-Tasman flights until at least midday Thursday, and Jetstar has also cancelled all its domestic services.
Pacific Blue says it has cancelled all services to and from Australia and the Pacific Islands until further notice.
There has been no disruption to Air New Zealand services, with the national carrier continuing to fly around New Zealand and to and from Australia. However, the airline says it is regularly reviewing the situation.
Major airlines in Australia began trying to clear a massive backlog of passengers after resuming flights across most of the country's southeast on Wednesday afternoon.
The CAA's meteorological manager, Peter Lechner, says the cloud stretches across the Tasman Sea to the eastern seaboard of Australia.
He says that gives airlines scope to fly under and around the cloud, but as it settles over New Zealand, getting around it will become increasingly difficult.
