Prime Minister Shinzo Abe plans to visit Ukraine and Germany from June 5 to 9, government officials said.
It will be the first visit to Ukraine by a Japanese prime minister.
Abe plans to hold talks with President Petro Poroshenko on June 6 in Kiev, the officials said Tuesday.
He is scheduled to attend a summit June 7 and 8 of the Group of Seven industrialized nations at Schloss Elmau, south of Munich in southern Germany, they said.
In his talks with Poroshenko, Abe is expected to express support for a cease-fire reached in February between the Ukraine government and pro-Moscow rebels, and urge all parties involved to de-escalate tensions over Russia's annexation of the Crimean region of Ukraine in March 2014.
While stressing opposition to any attempt to change the status quo by force, Abe is expected to underline the importance of coordinating with the United States and Europe over sanctions on Russia.
At the same time, he plans to refer to the need to hold dialogue with Moscow in an attempt to seek a diplomatic solution to the crisis.
At the G-7 summit, the leaders of Britain, Canada, France, Germany, Italy, Japan and the United States plan to focus on global and regional issues such as the situation in Ukraine, China's rising territorial ambitions in the East and South China seas, the world economy and climate change, according to the officials.
Abe will officially tell his counterparts the site of the G-7 summit that Japan will host next year.