'These separatists are armed by Russia': Pres. Obama blames Putin for MH17 attack

Barack Obama tonight accused Russia of supplying arms to the separatist rebels which blasted flight MH17 out of the sky over Ukraine - killing on 298 passengers on board.

The US president's intervention came as Downing Street said that it appears 'increasingly likely that MH-17 was shot down by a separatist missile' fired from near Torez, an area controlled by pro-Russian rebels.

Earlier, David Cameron warned that those responsible for the missile attack would pay, as the number of Britons thought to have been killed increased to 10. He is still seeking to speak to Mr Putin about the incident, according to Downing Street.

Mr Obama said Russia had provided 'a steady flow of support' for the rebels - including anti-arms aircraft'. 

His remarks came after the UK's representative at the UN, Ambassador Peter Wilson, blamed 'the senseless violence of armed separatists and with those who have supported, equipped and advised them' for the attack.

The US ambassador to the United Nations, Samantha Power, added that it cannot be ruled out that Russian personnel helped in the downing of the flight. 

Mr Obama, speaking from the White House, said: 'Evidence indicated that the plane was shot down by a surface-to-air missile that was launched from an area controlled by Russian-backed separatists inside of Ukraine.'

He added: 'We know these separatists have received a steady flow of support from Russia.' 

The remarks came after Mr Cameron promised to go after those responsible for the atrocity. He said those behind the missile attack needed to be 'brought to account', adding: 'It cannot be allowed to stand.'

Earlier, Ukrainian Prime Minister Arseniy Yatsenyuk urged Western leaders to 'bring justice to those b*******' who brought down the flight. He said world leaders needed to realised there was 'a war in the heart of Europe' taking place, amid growing fury at Moscow's backing the pro-Russian separatists suspected of carrying out the assault.

But Russian president Vladimir Putin called for a ceasefire between pro-Russian gangs in control of the area around Donetsk and the Ukrainian government. He said what was happening in Ukraine was 'awful - it's a tragedy'. 

But at the UN, Britain and the US openly blamed Russia for the tragedy.

The UK's Ambassador Wilson said: 'Russian officials have claimed armed separatists in eastern Ukraine represent the spontaneous local insurgency.

'We know that that is not the case. We know that the three leading figures of the so-called Donetsk People's Republic are Russian citizens and have come from outside Ukraine.

'We know that weapons, equipment and logistical support has been systematically provided to armed separatist groups by Russia.'

He added: 'We urge Russia to cease its policy or supporting armed separatist groups and their violent actions, of destabilising a neighbouring country, of generating displacement and social and economic hardship.

'Let us hear today clear and unequivocal condemnation from Russia of the actions of these armed groups. These armed groups do not represent the people oif Ukraine. Without Russian support they would wither.

The remarks came after Ukrainian leaders said the attack proved the need to toughen up the diplomatic pressure on Moscow. 

Prime Minister Yatsenyuk called for a UN Security Council meeting to be held and for nations to do 'everything we can to stop this war - a war against Ukraine, a war against Europe ... this is the war against the world.'

Kiev mayor, Vitaly Klichko, added: 'The world must finally understand that in Ukraine, in the heart of Europe, is a war.'

Kiev Interior Ministry advisor Anton Gerashchenko said it was a 'terrible terrorist act organized by Putin by means of the terrorists'.