The cruise ship Azamara Quest expected to arrive at the Port of Tauranga at 5.30pm is under investigation for an alleged incident when it entered Tory Channel earlier this week.

A passenger on board says the 180m long ship passed within 30 meters of rocks on entering the channel from Cook Strait.

Azamara Quest. Photo: supplied.

The Azamara Quest had 652 passengers and 394 crew on board at the time.

Stuff reports a passenger on board the Azamara Quest says the ship came within 30 metres of rocks as it entered Tory Channel about 9.20am Wednesday.

Tory Channel is narrow, with steep hills on both sides, and deep. Water just inside the entrance is 25m deep, dropping off to 60m past the turn. The passenger said he could clearly see rocks from the ship.

The channel entrance is within the Port Marlborough pilotage district, meaning the ship had a Port Marlborough pilot on board at the time.

Maritime New Zealand spokesperson Sandra Ford says they are making preliminary inquiries, but it's not yet an investigation.

The Transport Accident Investigation Commission's website states it's investigating whether the passenger ship made contact with Wheki Rock in Tory Channel on Wednesday. Two investigators met the ship at Napier to begin the site investigation.

Wheki Rock is immediately west of the Cook Strait entrance near Okukari Bay and is marked with a green pillar and flashing green light at night.

Unlike most of the other cruise ships visiting Port of Tauranga this season, the Azamara Quest is making an overnight visit to the Port of Tauranga, scheduled to arrive 5.30pm Friday and depart 6pm Saturday.

Azamara Quest is owned by Azamara Club Cruises, a subsidiary of Royal Caribbean Cruises.

It's the first time the ship cruised in the Marlborough Sounds, as the company just started offering New Zealand tours.

The Azamara Quest arrives at Tauranga from Napier.