Former Prime Minister Tony Abbott has revealed that the “highest levels” of the Malaysian government have believed from “very early on” that the MH370 tragedy was a murder-suicide plot.

Abbott spoke in a new documentary that’s set to air this week and was Prime Minister when the plane disappeared over the South China Sea in 2014. He explained that it was made “crystal clear” to him within a week that the aircraft was deliberately downed by the pilot.

“My understanding – my very clear understanding – from the very top levels of the Malaysian government is that from very, very early on here they thought it was a murder-suicide by the pilot,” Mr Abbott said in the first part of Sky News’ documentary  MH370: The Untold Story  hosted by Peter Stefanovic.

“I’m not going to say who said what to whom. But let me reiterate – I want to be absolutely crystal clear – it was understood at the highest levels that this was almost certainly murder suicide by the pilot. A mass murder suicide by the pilot.”

Malaysia Airlines flight 370 was carrying 239 people, including six Australians, when it disappeared about 40 minutes into its flight from Kuala Lumpur to Beijing on March 8.

The pilot in command was 53-year-old Zaharie Ahmad Shah, whose parting words are chilling.

“Good night. Malaysian three-seven-zero,” were his last words to air traffic control before the plane dropped off the radar at 1:21am.

Despite the Malaysian government’s report saying that there was no evidence that the “competent” Zaharie hijacked his own aircraft, Abbott is firm that officials never mentioned alternative theories, such as a catastrophic fire or terrorist hijacking to him.

“I’ve read all these stories that the Malaysians allegedly didn’t want the murder-suicide theory pursued because they were embarrassed about one of their pilots doing this. I have no reason to accept that,” he told  Sky News.

“If it is a fact that the furthest reaches were not explored because of assumptions of a pilot who was no longer at the controls, I would say let’s ditch that assumption,” he said.

“Let’s assume that it was murder-suicide by the pilot, and if there is any part of that ocean that could have been reached on that basis that has not yet been explored, let’s get out and explore it.”

The two-part documentary investigation on Foxtel reveals ground-breaking new details about the MH370 disappearance.