Bridget Brink, the U.S. ambassador to Ukraine, said on Wednesday that Russia has shown weakness by announcing a mobilisation of its military reserves and setting out referenda in Russia-occupied territories in Ukraine.
"Sham referenda and mobilization are signs of weakness, of Russian failure," Brink said on Twitter.
"The United States will never recognise Russia's claim to purportedly annexed Ukrainian territory."
(Reporting in Melbourne by Lidia Kelly; editing by Matthias Williams)
