All aircraft in New Zealand were grounded on Tuesday after a fault in the South Pacific nation's air traffic control system, officials said.

"There has been a radar failure that has occurred at 2.48pm (0248 GMT) this afternoon, we are working on the issue at the moment," a spokeswoman for the government's Airways New Zealand, which manages air traffic control, told AFP.

"The impact is that all aircraft have been held on the ground. There are no aircraft taking off across the country. The aircraft that are in the air have been cleared to land."