President Vladimir Putin on Tuesday suspended Moscow's participation in a nuclear arms reduction treaty with Washington during a speech in which he accused the West of escalating the Ukraine conflict.

In his scathing state of the nation address to Russian lawmakers, Putin also vowed that Russia would keep fighting in Ukraine ahead of the first anniversary of the military campaign.

Accusing Western powers of wanting "to be done with us once and for all", he said Russia was "forced" to suspend the New START treaty but would not pull out of the agreement altogether.