People should not expect fares to continue to get lower and lower but should book their trips when they'd decided on their dates to avoid missing out.
Mr Cull said the recent low fares were as good as he had seen for a long time.
Despite the increasingly affordable international fares, domestic travel remained a challenge with cars and shuttles cheaper than a domestic flight to Tauranga.
Mr Cull thought Air New Zealand was considering increasing capacity to New Zealand regions where appropriate.
He hoped that would allow more people to fly to the Bay of Plenty.
An Air New Zealand spokesperson said 640 seats or 320 return trips across Los Angeles, San Francisco, Houston, Tokyo and Shanghai were made available on its Grabaseat website on Wednesday morning.
More than 200 trips had been snapped up by late Wednesday afternoon.