Japan's prime minister spoke to France's president on Tuesday to express Tokyo's support for sanctions against Russia over its "aggression" towards Ukraine.

- I agreed that Russia's aggression towards Ukraine undermines the very foundation of the entire international order and that it is imperative for the international community to unify in imposing stringent measures on Russia - premier Fumio Kishida said after the phone call with Emmanuel Macron.

Japan has joined its Western allies, including the US, UK, and EU, in imposing sanctions against Moscow to deter it from continuing its war against Ukraine.

- Japan will vigorously support Ukraine by working in cooperation with France and the rest of the international community - Kishida said on Twitter.

Since Russia's war on Ukraine began last Thursday, it has been met by outrage from the international community, with the EU, UK, and US implementing a range of economic sanctions on Russia.

So far, at least 136 civilians, including 13 children, have been killed and 400 others, including 26 children, injured in Ukraine, according to UN figures.

Around 660,000 people have fled Ukraine to neighboring countries, the UN Refugee Agency said on Tuesday.