Russia’s foreign minister, Sergei Lavrov, has said the four Ukraine regions where votes are under way in 'referendums' will be under Moscow’s 'full protection' if they are annexed by Russia.
At a news conference following his speech to the United Nations general assembly in New York, Lavrov was asked if Russia would have grounds for using nuclear weapons to defend annexed regions of Ukraine. 
The Group of Seven industrialised economies have said they will not recognise the results of the 'referendum' votes