Air New Zealand says it is taking the "unusual step" of restricting ticket sales and stopping all sales on some international flights as the jet fuel shortage bites.
It said the move would help it accommodate passengers whose flights have been cancelled due to the shut-down of Refining New Zealand's pipeline to Auckland.
More services are also being cancelled for tomorrow, including five Australian flights, two to Fiji and a return service to Ho chi Minh in Vietnam.
The airline cancelled four trans-Tasman and 26 domestic flights between Sunday and Wednesday after the fuel line from the Marsden Pt refinery ruptured on September 14.
Air New Zealand said in total it had cancelled 26 domestic, 11 Tasman and Pacific Island and two international long-haul flights.
Some 3000 customers will be hit by Wednesday's cancellations, and around 6000 disrupted by schedule changes.
Most passengers are being put on alternate services, the airline said.
Customers who already have flights booked should ensure their contact details have been included in their booking and should sign up for travel alerts.
Businesses and the Government are putting a number of measures in place to try to stay on top of the fuel crisis.
Auckland Airport has announced it is changing the flight paths of a number of services to help save around 2000L of fuel each day.
The Green X23A SMART Approach flight path to the airport is usually capped at 10 flights per day, but this has now doubled to 20 flights. The jetfuel savings are almost enough for one A320 to fly from Auckland to Wellington.
Cargo loads are also being reduced, Air NZ said.
"Air New Zealand will no longer accept ad hoc cargo shipments (other than urgent medical equipment) and any pre-arranged consignments heavier than the booked weight will not be accepted for carriage."
The Government has also relaxed rules around how much fuel can be carried on board tankers to increase the amount that can be trucked from the refinery in Ruakaka.
Company supply managers were also working with the Government today around the possibility of using tanks at Wynyard Wharf for fuel distribution. Fairfax reported traffic lights could be synchronised to move the trucks across Auckland as fast as possible.
Extra defence force road tankers are also being assessed for use in the fleet.
FUEL COMPANIES SAY GROUND FUEL SUPPLIES 'HEALTHY'
Customers of Refining New Zealand said today that there was "no shortage of petrol or diesel in and around Auckland".
A statement from the company's customers said ground fuel supplies were "healthy".
Andrew McNaught, manager of Mobil NZ and spokesman for Refining New Zealand's customers, said the industry's focus was on ensuring ground transport fuels were safely, securely supplied to Auckland.
But a shipping schedule for the next few days would also provide confidence around the national fuel supply position, particularly to those airports which are supporting Auckland Airport and need jet fuel supplies.
The Marsden Point refinery is continuing to produce fuel and the two dedicated coastal shipping vessels are continuing to load at the refinery for distribution around the country's ports, according to a statement from Refining NZ's customers.
• The coastal vessel Matuku was arriving in Tauranga today. Cargo totalling 39,200 metric tonnes was comprised of premium petrol, regular petrol, diesel and bunker fuel oil.
• The second vessel, Kakariki, was loading at the refinery today and leaving for Lyttelton, where it will arrive early on Friday morning. It has premium petrol, regular petrol, jet, diesel, bunker fuel oil and bitumen on board. The Kakariki will then continue south to Dunedin, resupplying all grades.
• An import vessel will arrive in Tauranga on Thursday to discharge regular petrol and diesel. It will then travel to Lyttelton, arriving on Sunday, to deliver additional regular petrol, jet and diesel, before travelling to Bluff to discharge regular petrol and diesel.
• Another import vessel will arrive in Lyttelton on Saturday, where it will discharge jet fuel. It will then go to Wellington where it will discharge regular petrol. It will then go across the harbour to Wellington Airport and fill all of the jet tanks to tank tops.