Malaysia's prime minister on Thursday said he was unsatisfied with the latest report from international investigators that implicated Russia and charged four pro-Russian rebels over the downing of Malaysia Airlines flight MH17 in eastern Ukraine in 2014, describing it as politically motivated.

Mahathir bin Mohamad was reacting to Wednesday's report from the Joint Investigation Team in charge of the MH17 probe.

The board of investigators, based in the Netherlands, charged four pro-Russian rebels with murder for their alleged role firing a Buk surface-to-air missile at the passenger plane conflict zone in eastern Ukraine on July 17, 2014, killing all 298 passengers and crew aboard.

"We are very unhappy because from the beginning it became a political issue on how to accuse Russia of the wrongdoing before they examined," the PM told reporters, as cited by state news site Bernama.

"From the very beginning, they wanted to accuse Russia and now, of course, they said they have proof who the person is. This is a ridiculous thing," he added. "We want proof of guilt but so far no proof," Mahathir said.

Dutch authorities have issued an arrested warrant for Igor Girkin, Sergey Dubinsky, Oleg Pulatov and Leonid Karchenko.

Girkin was the so-called Donetsk People Republic's defense minister when flight MH17 was downed, Dubinsky was his deputy and a former member of Russia's GRU intelligence service, Pulatov was head of the DPR's intel service and Karchenko, who has no military background on record, commanded a unit in Donetsk.

The suspects will be tried in the Netherlands either in person or in absentia in a procedure beginning Mar. 9, 2020.

The JIT, which comprises experts from the Netherlands, Belgium, Australia, Malaysia and Ukraine, said the first three suspects were Russian and most likely lived in Russia, while Karchenko was Ukrainian and probably lives in rebel-held Ukraine.

According to the JIT, the Buk missile used to down the craft belonged to the Russian military and had been transported to the breakaway region of eastern Ukraine across the Russian border. After it was fired, the JIT said, it was returned across the frontier.

Russia has vehemently denied all accusations implicating it in the tragedy.

On Thursday, the Russian defense ministry said in an online statement that none of its air defense missile systems had ever crossed the border between Russia and Ukraine.

Eastern Ukraine descended into violence in 2014 when pro-Russian insurgents grabbed power and created the de facto DPR and the Luhansk People's Republic as the country reeled from a pro-European revolution that ousted the former Russophile president, Viktor Yanukovych.

The unrest, which according to the United Nations has claimed more than 10,000 lives, came after Russia's annexation of Crimea. EFE-EPA