"The shut-down is currently impacting all airlines operating into and out of Auckland Airport and limiting the volume of jet fuel able to be uplifted to 30 per cent of normal usage.
"It's estimated around 2000 Air New Zealand customers will be affected by flight cancellations today as the airline works to consolidate passenger loads and minimise fuel usage."
Some long-haul services to and from Asia and North America were refuelling at selected Pacific or Australian airports.
"The airline is also ensuring domestic jet services uplift maximum fuel limits when operating out of Wellington or Christchurch to limit refuelling in Auckland."
Aviation was a critical transport industry "and the lifeblood for tourism and we are naturally extremely disappointed with this infrastructure failure", he said.
Meanwhile two codeshare flights, being operated by other airlines, due in from Sydney at 12.20pm has been cancelled along with one due to depart across the ditch at 1.10pm.
Three flights due to land from Melbourne at 2.15pm, involving Air New Zealand, Singapore Airlines and Virgin Australia, were earlier cancelled.
Meanwhile, Refining NZ chief executive Sjoerd Post this morning told Radio New Zealand reports that a digger striking a kauri log caused the pipeline bust was "fake news".
The company was also "absolutely sorry" for the disruption, he told the broadcaster.
He also estimated close to 60,000 litres - or 1 to 1.5 truckloads - of fuel leaked during the incident.
An airport spokesperson said there have been a few new domestic cancellations, however due to the volume of flights between Wellington, Auckland and Christchurch many passengers would likely be put on other flights. A Blenheim flight has also been affected.
The spokesperson saidthere were currently 14 international or domestic flights cancelled.
However, when put in context that an average of more than 460 flights went in and out of the airport daily, the impact hadn't been too bad.
"I think contextually wise, we have 465 flights that operate at the airport daily so if you look at it with that context there's not a huge amount of flights that have been cancelled.
"What that shows is that airlines have responded and have put in mitigation and are refuelling and using other measures."
She disputed reports of "thousands" of passengers being affected by the incident today as many of the 14 flights were not full and passengers would be put on to other planes travelling on the same day.
The spokesperson said the delays would still be frustrating for affected travellers.
"Obviously there's delays because of the refuelling at other places or they're coming into the country a bit later because they're refuelling on the way in, so there's still delays and I can't tell you at the moment how many of those there will be."
The cancellation or delay of flights was quite a fluid situation and the decisions were made by the airlines, not the airport, so she urged passengers to continue to check its website for updates.
Meanwhile, deputy Prime Minister Paula Bennett was distancing her government from the situation while being grilled by Guyon Espiner on Radio NZ this morning, stating they shouldn't be blamed for a crisis caused by a private company.
"I don't think that everything is the Government's fault which you're trying to blame us for a pipeline that's gone down in really unexpected circumstances that we don't own ... but we can look at it ... and will be willing to make changes as they need to and throw everything that we've got on it at the moment to make sure that it's up and running."
She said National's campaign won't be hindered by the cancellation of flights as they're travelling by bus around the countryside.
"We've got a bus, you'll be pleased to know, Guyon. There's nothing wrong with the National Party bus."
The Northland Regional Council was advised of the spill about 3pm on Thursday.
A council spokesman said staff responded immediately, carrying out an extensive site assessment over several hours and assisting refinery workers with initial containment of the spilled fuel.
Staff would now get samples from groundwater bores to establish existing water quality parameters but council didn't believe they would be impacted "given the prompt nature of the containment, recovery and clean-up".
"At this stage, council is satisfied the refining company acted promptly and appropriately, both in its notification of - and subsequent response to - the leak."
The council would investigate whether any enforcement or prosecution under the Resource Management Act was warranted.
Tourism companies have been fielding calls from worried travellers about the impact it will have on them, especially in the lead up to school holidays in two weeks' time.
The Government has offered to help oil companies struggling with the aviation fuel crisis that threatens to disrupt air travel out of Auckland for up to two weeks.
All flights coming into Auckland have been advised to carry enough extra fuel to get out again. Long-haul flights are being redirected to refuelling stops at other NZ or international airports as oil companies predict it could take 10 to 14 days to restore normal supplies.
Anyone due to fly out from Auckland Airport is urged to check the airport's arrival and departure schedule for updates.