However the investigators could not say who 'pushed the button' to launch the missile: whether it was Ukrainian separatists, or Russian soldiers working with them.

The new analysis comes as Prime Minister Tony Abbott prepares for his long-anticipated face-to-face encounter with Russian president Vladimir Putin over MH17: either at an APEC conference in Beijing on Monday and Tuesday, or at this weekend's G20 meeting in Brisbane.

Mr Abbott promised last month to 'shirtfront' Mr Putin, saying "Australians were murdered… by Russian-backed rebels using Russian-supplied equipment".

Mr Abbott has since toned down his language, saying last week he would tell Mr Putin that "Australia expects full Russian cooperation with the investigation" into the crash.

MH17 was shot down over separatist-held eastern Ukraine on July 17, killing 298 people including 38 Australians.

Since July the 'Bellingcat' project, launched by British investigative journalist Eliot Higgins, has gathered photographic, video and eyewitness evidence and analysed it with a team of citizen journalists brought together through social media.

The team used sophisticated tools, such as satellite imagery and a computer program that recreated the angle of shadows in a particular place to pin down exactly what time of day a photograph was taken.

'Undeniable evidence'

They claim that much of the material they analysed was "overlooked" by other organisations investigating the crash.

"There is undeniable evidence that separatists in Ukraine were in control of a Buk missile launcher on July 17th and transported it from Donetsk to Snizhne [a town close to the crash site]," the team wrote in their report, published online on Saturday.

"The Buk missile launcher was unloaded in Snizhne approximately three hours before the downing of MH17 and was later filmed minus one missile driving through separatist-controlled Luhansk."

The team said the same Buk was part of a military convoy that had travelled from the Russian town of Kursk to the Ukraine border, between June 22 and June 25.

"There is strong evidence indicating that the Russian military provided separatists in eastern Ukraine with the Buk missile launcher filmed and photographed in eastern Ukraine on July 17," the report concluded.

Using photographs and videos posted to social media sites soon after the crash, the team mapped the route of the Buk missile launcher through separatist-controlled territory on July 17.

They also claim to have debunked Russian propaganda that had tried to undermine the credibility of some of the evidence they used.

They matched some of the features in photographs of the June Russian military convoy, with features on the missile launcher spotted on July 17 in Ukraine – including paint marks and a unique pattern of damage to the side of the vehicle.

New investigation milestone 

Further evidence suggests that after the crash the missile launcher convoy then headed for the Russian border.

Veli-Pekka Kivimäki, a computer software engineer from Finland, is a member of Bellingcat's six-person team looking into the MH17 crash, which compiled the report.

His role included geo-locating the different videos taken of the missile system in Russia and Ukraine.

He told Fairfax their work was still continuing, however there was a sense they had reached a milestone, being able to "pretty reliably" link the Russian convoy to the missile that brought down MH17, he said.

"We have established with reasonable certainty that the missile system that was on the move in Ukraine on July 17th came from Russia," he said.

"We believe it was in the control of separatists forces at that time (of the crash)… (on) the aspect of who 'pushed the button'; many have suggested it's Russian forces working with separatists, but on that we do not have conclusive information."

Mr Kivimaki said his team had seen misinformation put out about the MH17 crash, but they had a "pretty good sense" which material was genuine.

"We have material from ordinary people who didn't necessarily know what they were looking at but they saw something interesting, they photographed it or videoed it," he said.

"Then taking these things from multiple sources, multiple platforms and piecing the big picture together, I think we have pretty good reliability that what we have is authentic and does not come from a poisoned source."

The team had looked at alternative theories, such as claims that the missile had been seized from a Ukraine base, but satellite images had shown no significant movement in and out of the base it could have come from, Mr Kivimaki said.

Asked if other intelligence agencies had asked to see Bellingcat's work, Mr Kivimaki said he could not comment, but he was sure that the official investigation into the crash would look at all the available evidence.

An official investigation into the crash, by an international team based in the Netherlands, is yet to hand down its conclusions.

A preliminary report said damage to the plane was consistent with a missile attack but did not make any claim as to the source of the missile that brought down the plane.

On the weekend Dutch foreign minister Bert Koenders said the remains of the last nine victims of flight MH17 may never be recovered.

He made the comment at a memorial service in Kharkiv for five more sets of human remains collected from the site of the disaster in the last week.

"We cannot say at this moment in any certain way … at what moment, and even if, we can recover the last nine" victims, he said.

with AFP