The decision to ground the planes was made after an - All Nippon Airways - flight was forced into an emergency landing.

Three national aviation regulators are now undertaking safety investigations, although Boeing insists the plane is safe.

All Nippon and its rival Japan Airlines are among Boeing's biggest customers for the Dreamliner -- they have both said they will ground the entire 787 fleet pending safety checks.

Boeing has more than 800 Dreamliners on order around the world.