The UK has called for an urgent meeting of the UN Security Council to discuss the poisoning of a former double agent in Salisbury, the Foreign Office says.
Russia failed to respond to a midnight deadline set by Theresa May to explain how a Russian-made nerve agent was used on Sergei Skripal and daughter Yulia.
The PM is set to announce a series of measures against Russia before MPs later.
Russia said it had “no motive” in the attempted murder of the pair.
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