British Foreign Secretary Boris Johnson has said Russia's actions in Syria may amount to war crimes if the country was involved in an airstrike on a humanitarian aid convoy near Aleppo.
Johnson made the statement while appearing on the BBC's Andrew Marr show on Sunday.
The attack last Monday left 20 people dead and also destroyed a warehouse, and while the US believes Russia is behind the attack, no one has claimed responsibility.
Russia fired back at the accusations and blamed rebel shelling or a US drone strike.
Boris Johnson appeared to suggest the incident may have been deliberate. "Putin’s regime is not just handing Assad the revolver," the foreign secretary told Marr. "He is in some instances firing the revolver. The Russians themselves are actually engaged."
"We should be looking at whether or not that targeting is done in the knowledge that those are wholly innocent civilian targets. That is a war crime."
The attack followed the collapse of a cease-fire brokered by the US and Russia, and prompted the UN to suspend all aid convoys to Syria.
Johnson also alarmingly admitted that the west has failed to orchestrate a coherent "response to what is going on" in the country where — according to official UN estimates— more than 400,000 have died since the outbreak of a major civil war in 2011.
Speaking to Marr, he said: "If you say to me the west is too impotent, I would have to agree. I would have to agree that, since we took those decisions in 2013 when those red lines were crossed, we have not really had a viable military response, or any kinetic response to what is going on."
He also stressed the UK is "in the lead" on tightening sanctions against Russia but claimed that the one thing that Russians respond to is being publicly shamed.
"The idea they are in the dock of the court of international opinion" is one of their fears he said. "They are guilty of making the war far more protracted and far more hideous."
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