Volunteer observers aboard Australian jets deployed in the hunt for the missing Malaysia Airlines flight MH370 have sighted a number of small objects, possibly aircraft debris, with the naked eye.

The Australian aircraft, including commercial jets, have been scouring the remote southern Indian Ocean for the wreckage and this will be the first-ever visual confirmation of the plane, if it is known for certain that the latest sightings are related to the vanished Malaysian jetliner.

The Australian Maritime Safety Authority (AMSA) said in an early morning statement: "During Saturday's search actives a civil aircraft tasted by AMSA reported sighting a number of small objects with the naked eye, including a wooden pallet, within a radius of five kilometres."

"A Royal New Zealand Air Force (RNZAF) P3 Orion aircraft with special electro-optic observation equipment was diverted to the location, arriving after the first aircraft left but only reported sighting clumps of seaweed. The RNZAF Orion dropped a datum marker buoy to track the movement of the material. A merchant ship in the area has been tasked to relocate and seek to identify the material."

Australian satellites had sighted floating objects in a stormy remote stretch of the southern Indian Ocean, thousands of kilometres off Perth, which was followed by sightings by Chinese satellites as well.

Australian Prime Minister Tony Abbott has said there is "increasing hope" that the search activities in the Indian Ocean will be fruitful but warned the objects might be unrelated to the Malaysian airliner.