Malaysian authorities are uncertain what to do with the black boxes from Flight 370 if they are located and brought to the surface from the Indian Ocean north-west of Perth.

The country’s Attorney-General Abdul Ghani Patail has flown to London to consult with the United Nations Civil Aviation Organisation and other experts about who should get custody of the boxes.

Under an international treaty, Malaysia is head of the investigation into the disappearance of the plane with 239 people on board on March 8. But facing accusations of incompetence in the largest and most complex investigation in its history, the government in Kuala Lumpur has called in international experts from countries including the US, Britain and France to join local investigators.

Australia has also been delegated to lead a multi-nation search of the southern Indian Ocean where the Boeing 777 is believed to have crashed after running out of fuel.

Malaysia’s acting Transport Minister Hishammuddin Hussein declined to elaborate on Mr Abdul Ghani's talks.

“I would like to address that when we actually do find the black box,” he said.

Experts say finding the recording devices will be crucial to unravelling the mystery of what happened aboard the flight that was scheduled to fly from Kuala Lumpur to Beijing. But they say the cockpit voice recorder inside them may not be helpful because they store only about two hours of sound and probably have not preserved what was being recorded around the time the plane was diverted thousands of kilometres off course while over the South China Sea.

In two previous air crash findings that were based partly on black box examinations, Singapore and Egypt, the owners of the planes never accepted American findings that the causes were pilot murder-suicides.

The agency with the most experience in examining Boeing black boxes is the National Transportation Safety Board in Washington. But Malaysia’s government has been forced to dampen strong anti-US sentiment in the country in recent days despite Washington assigning at least 12 investigators to join the criminal investigation and FBI forensic experts examining the home flight simulator of senior pilot Captain Zaharie Ahmad Shah.

The Utusan Malaysia newspaper, which is owned by the ruling United Malays National Organisation, published a report last week linking the Central Intelligence Agency to the plane’s disappearance, without providing any evidence. The report claimed the CIA wanted to sour ties between Malaysia and China.

The Malaysian government took several days to deny the claim. Asked about the report at a defence services exhibition, Mr Hishammuddin said if there was any link to the CIA “I don’t think we will see such a strong presence of the US here.”

“Like any Western media too, they [Utusan Malaysia] are free to report what they like to report,” he said. “But at the end of the day, if their reporting is false, they lose credibility.”

Authorities in Kuala Lumpur insist they will not release any information about the investigation while it is ongoing.

“I do not want to disrupt the investigations that are being done now, not only by the Malaysian police but by the FBI and [British intelligence service] MI6 and the Chinese intelligence and other intelligence agencies,” Mr Hishammuddin said.