A train carrying the remains of some of the nearly 300 victims of the Malaysia Airlines plane downed over Ukraine was heading for Ukrainian government territory today as a separatist leader handed over the plane's black boxes to Malaysian experts.

Dutch Prime Minister Mark Rutte said that the train carrying around 200 body bags was on its way to rebel-held Donetsk and then to Kharkiv, which is in Ukrainian government hands, from where the bodies would be taken back to the Netherlands to be identified.

The train left the crash site after the Malaysian prime minister reached agreement with the separatists for recovered bodies to be handed over to authorities in the Netherlands, where the largest number of victims came from.

Early today, senior separatist leader Aleksander Borodai handed over the black boxes in the city of Donetsk.

"Here they are, the black boxes," Borodai told a room packed with journalists at the headquarters of his self-proclaimed Donetsk People's Republic.

Colonel Mohamed Sakri of the Malaysian National Security Council told the meeting the two black boxes were "in good condition".

Shaken by the deaths of 298 people from across the world, Western governments have threatened Russia with stiffer penalties for what they say is its backing of pro-Russian militia who, their evidence suggests, shot the plane down.

At the United Nations, the Security Council unanimously adopted a resolution demanding those responsible "be held to account".

"We owe it to the victims and their families to determine what happened and who was responsible," said Australian Foreign Minister Julie Bishop. Australia lost 28 citizens in the crash.

penalties

European Union foreign ministers are today to discuss further penalties against Russia, but the most they are expected to do is to speed up implementation of sanctions against individuals, and possibly companies, agreed in principle last week before the plane was brought down.

Western leaders struggled to come to a united response against Moscow.

Diplomats say more serious sanctions against whole sectors of the Russian economy will depend largely on the line taken by the Dutch, because of the high number of Dutch victims.

"It is clear that Russia must use her influence on the separatists to improve the situation on the ground," the Dutch prime minister said.

"If in the coming days access to the disaster area remains inadequate, then all political, economic and financial options are on the table against those who are directly or indirectly responsible for that," said Rutte.

US President Barack Obama said it was time for Mr Putin and Russia "to pivot away from the strategy that they've been taking and get serious about trying to resolve hostilities within Ukraine".

He said Mr Putin and Russia had a direct responsibility to compel separatists to cooperate with the investigation, and that the burden was on Moscow to insist that separatists stop tampering with the probe, he said.

"What are they trying to hide?" Mr Obama said at the White House.

Australian Prime Minister Tony Abbott described what was happening at the scene as a cover-up.

"After the crime, comes the cover-up. What we have seen is evidence tampering on an industrial scale," Mr Abbott said.

hnews@herald.ie