Japanese gas and energy firms are closely monitoring the developments of Russia's aggression in Ukraine, with some eyeing non-Russia players as alternative suppliers amid concerns Moscow may reduce or suspend its natural gas supply in retaliation for Western sanctions on the country.

To prepare for potential supply disruptions from Russia and other emergencies, Hiroshima Gas Co. is considering purchasing liquefied natural gas (LNG) from Malaysia and other producers, while Osaka Gas Co. plans to bring forward gas procurement from the United States or Australia.

Russian President Vladimir Putin has also surprised Japanese energy companies by saying Russia will seek payment in rubles, not the dollar or euro as commonly used, for gas sales from "unfriendly countries" such as Japan and the U.S., which have been imposing sanctions on Moscow.