Russia has unleashed a blistering war of words against Britain at the UN Security Council. Moscow's ambassador denied accusations over the poisoning of a former double agent in England. Earlier, Britain blamed Russia for the poisoning of Sergei Skripal and his daughter Yulia in Salisbury. More than two dozen Western allies have expelled over 150 Russian diplomats in a show of solidarity. Russia has requested an open meeting over the investigation. Our UN Correspondent Liling Tan has more from New York.