Passengers faced long lines at Auckland Airport after a security "breach" (file photo).

Flights out of Auckland Airport were delayed after a security "breach" on Sunday afternoon.

An Auckland Airport spokesperson said security processing at the airport was temporarily shut down.

All international departures from the airport were held up for about 30 minutes, as passengers stood waiting to be processed.

"Aviation security had a breach, so that halted screening and as a result also held up international flight departures," the spokesperson said.

"Now it's all been resolved."

The spokesperson didn't have any further details about the breach or how many flights were affected.

A traveller contacted Stuff saying the lines were "huge" during the security shut-down.

The airport's Aviation Security Service has been contacted for comment.