Air New Zealand has filed court proceedings against BP and Z Energy for damages caused by last year's fuel-pipeline rupture north of Auckland.
The rupture caused fuel shortages and hit airlines hard as the fuel-pipe carries nearly all of Auckland's aviation fuel to the airport.
The fuel pipeline owned by Refining NZ, which runs from the Marsden Point refinery to Wiri in South Auckland, ruptured last September.
An investigation found the pipe was weakened after it was scraped by a digger in the three years leading up to the breach.
Z Energy said it has received a statement of claim from Air New Zealand Limited for $4.3 million for the cut in supply.
"The proceedings will be defended and Z refutes all claims," Z Energy stated.
"Given the proceedings are now before the court, Z will not be making any further comment."
BP said it would also dispute the claims - it was unclear how much Air New Zealand was seeking from BP.