UPDATED 9.23AM: One of Auckland's hottest dining spots became a little too hot this morning.

The O'Connell Street Bistro - a mainstay of the city's rich and famous - has been damaged by fire.

The alarm was raised after a neighbouring building's alarm was set off just before 4am.

Six fire crews were called and the blaze on the ground floor. Station Officer Peter Cranwell says the fire was put out relatively quickly, and a team is now investigating the case.

A thick smell of burning plastic hung in the morning humidity as crews began packing up just before 5am.

The restaurant's owner Chris Upton was this morning sorting through the damage.

"It appears there's been some form of fire within the front of the kitchen. We don't know what it is yet. It's pretty substantial damage," he said.

The O'Connell St Bistro, on the corner of Shortland and O'Connell Streets, has won a host of industry awards and bagged rave reviews from international publications including the New York Times.

The intimate European-inspired eatery is known for its elegant menu and private dining room where prime ministers, royalty and celebrities have enjoyed meals hidden from public gaze.