Over 3,000 square kilometres in the southern arch of the Indian Ocean has been searched for the Malaysia Airlines MH370 aircraft, which went missing on March 8, according to the Australia Joint Agency Co-ordination Centre (JACC).

In a statement that was made available to Bernama Wednesday, JACC said the underwater search was aimed at identifying any crucial evidence, such as aircraft wreckage and flight recorders, to assist the Malaysian investigation.

"The ATSB (Australian Transport Safety Bureau) has utilised the data from the bathymetric survey work to prepare the initial plan for the underwater search, to be followed and referred to by all parties involved," said the agency.

It said the plan included search timings, methods, procedures, safety precautions and search areas.

"The initial search areas have been allocated to the different vessels with the aim of positively identifying and mapping the debris field of MH370," the agency said.

JACC said the current bathymetric survey work was completed on Oct 26 and all data had been analysed with a total area mapped of over 160,000 sq km of the Indian Ocean.

The agency also said the Malaysian contracted vessel, GO Phoenix, had commenced underwater search operation on Tuesday.

Flight MH370, which was carrying 227 passengers and 12 crew members left the KL International Airport at 12.41am on March 8, and disappeared from radar about an hour later while over the South China Sea.

It was to have arrived in Beijing at 6.30am on the same day.

The search for the aircraft is ongoing, with no concrete evidence being found yet.