The world's largest fishing vessel, the factory freezer ship Lafayette, has turned up in the Pacific Ocean east of Australia.

Satellite-tracking systems registered the location of the controversial 49,000 tonne Lafayette and six attendant trawlers north-east of Norfolk Island on Friday, Greenpeace said.

Fear: Lafayette alarms Greenpeace.

The Russian-flagged, Chinese-owned vessel is five times the size of the Dutch factory trawler Margiris, which was banned from Australian waters in 2012.

''It should be very worrying to the region that a vessel of the size of Lafayette would target fish in the South Pacific,'' Greenpeace campaigner Nathaniel Pelle said.