Defence Secretary Michael Fallon has accused Russia of "sponsored terrorism" and insisted it must "get out of east Ukraine" after the flight MH17 disaster.
Mr Fallon said there would be "repercussions" if it turns out Russian-backed rebels were behind the shooting down of the airliner which left 298 people dead.
'We have to make it very clear if there is any more interference like this - and it turns out he was behind it - there will be repercussions," Fallon told the Mail on Sunday.
"If Russia is the principal culprit, we can take further action against them and make it clear this kind of sponsored war is completely unacceptable."
Claiming Russian president Vladimir Putin was "egging on" the rebels, Mr Fallon added: "It is sponsored terrorism as far as people of east Ukraine are concerned. We don't know if somebody said, 'let's bring down a civil airliner, wherever it's from', - but we need to find out.
"They need to get out of east Ukraine and leave Ukraine to the Ukrainians."
Thousands of online users have taken to social media to call for the victims of the Malaysian airliner crash to be returned to loved ones.
United States intelligence officials admitted that they do not know who fired the surface-to-air missile that downed flight MH17.
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