Fallon blames Russia for Assad's deadly gas attack
Russia is responsible for "every civilian death" in Bashar Assad's chemical weapons attack on his own people, the Defence Secretary has said.
Sir Michael Fallon said Vladimir Putin's Kremlin was to blame "by proxy" because it was the Syrian president's "principal backer".
His comments came after Foreign Secretary Boris Johnson pulled out of a Moscow visit hours before he was due to fly.
Some 87 people, including children, are believed to have been killed in a suspected sarin nerve agent strike on the rebel-held town of Khan Sheikhoun.
US president Donald Trump ordered a strike by 59 cruise missiles on the base he said launched the attack, in America's first direct attack against the Syrian government.
Writing in the Sunday Times, Sir Michael said Russia must be part of the solution to end the "needless suffering" of Syrian civilians.
"But Assad's principal backer is Russia. By proxy, Russia is responsible for every civilian death last week," he said.
"If Russia wants to be absolved of responsibility for future attacks, Vladimir Putin needs to enforce commitments to dismantle Assad's chemical weapons arsenal for good, and get fully engaged with the UN peacekeeping progress."
He also reiterated his support for Mr Trump's cruise missile strike in the early hours of Friday, UK time.
"By sending Tomahawk missiles to attack the airfield, it has sent a strong signal to the Syrian regime to think twice before using gas in the future," he wrote.
But there must now be a long-term solution to the civil war in which Assad must no longer be president, he added.
"Someone who uses barrel bombs and chemicals to kill his own people simply cannot be the future leader of Syria," he said.
Mr Johnson is to spearhead demands for Russia to withdraw its forces from Syria when he meets G7 leaders in Italy next week.
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