Air New Zealand has started the painful process of slashing more of its workforce

Thirteen hundred workers will lose their jobs with Air New Zealand announcing staff cuts affecting all routes.

A third of the airline's 12-thousand-500 staff may go - as Covid-19 takes a toll on the airline's revenue.

In an email to staff and air-points members last night, chief executive Greg Foran says the only flights remaining are in place to keep supply lines open and transport options for essential services personnel.

He says Covid-19 has seen the airline go from having revenue of five point eight billion dollars, to what is shaping up to be less than 500 million annually.

Air New Zealand's refusing to comment.