A move by Japan to hand over Patriot air defence systems to Ukraine will have "grave consequences" for Russia-Japan ties, Russian foreign ministry spokeswoman Maria Zakharova said on Wednesday.

Relations between Moscow and Tokyo, already difficult, have deteriorated sharply since Russia sent tens of thousands of troops into Ukraine in Feb. 2022. Japan has joined its Western allies in imposing sweeping economic sanctions on Russia. (Reporting by Dmitry Antonov Writing by Olzhas Auyezov Editing by Gareth Jones)