WELLINGTON, New Zealand — New Zealand's transport minister said Monday he will pay a small fine for violating aviation rules by making a cellphone call from a plane.

The Civil Aviation Authority fined Phil Twyford 500 New Zealand dollars ($340) for breaching rules it says were intended to prevent electromagnetic interference with aircraft instruments.

The authority said that because Twyford ended his call before takeoff, it didn't pose a significant risk to the safety of the flight.

Twyford had earlier stepped down from his role overseeing aviation safety after making the call to a staffer in May.

Acting Prime Minister Winston Peters said the breach was a low-level offense and that Twyford was contrite and would be reinstated to his aviation oversight role now the investigation was complete.

"A slight irony, of course, is that we have noticed that a great number of other people are guilty of that offense," Peters said. "It should be a great deal of education value to us all to know how serious it is."

Twyford said Monday he can't recall the exact chronology of the call, but that his phone records and airline records indicated he'd been on the phone for about three minutes while the plane was taxiing but before takeoff.

Cellphone calls are banned after the doors are closed in preparation for takeoff. While some rules around mobile devices have been relaxed in recent years, passengers are still banned from making cellphone calls or sending text messages during flight.

"I'll be paying the bill very shortly," Twyford said. "It was a breach, and particularly inappropriate given that I'm the transport minister."

He said he wanted to reiterate his earlier "unreserved apology" for his mistake.

The breach was brought to light by an opposition lawmaker.