MOSCOW: Russian Foreign Minister Sergei Lavrov said yesterday London cannot ignore Moscow's "legitimate questions" over the poisoning of an ex-spy, as he called for a "substantial and responsible" probe into the case, reports AFP. "It will not be possible to ignore the legitimate questions we are asking," he said hours before a meeting of the UN Security Council, which is due to discuss the spiralling diplomatic crisis between Russia and the West.

Moscow is insisting on a "substantial and responsible investigation" in accordance with the Chemical Weapons Convention, Lavrov added. London has said it is highly likely that Russia is to blame for the poisoning of former double agent Skripal and his daughter Yulia in the English city of Salisbury on March 4.

Moscow has angrily denied any involvement.

The row has resulted in a massive wave of diplomatic expulsions by Britain and its allies and then by Russia in a tit-for-tat move.

Russia called a meeting of the global chemical watchdog on Wednesday over the Salisbury incident, but failed in its bid to join the probe by the Organisation for the Prohibition of Chemical Weapons (OPCW).