Russia's Foreign Ministry said it will suspend negotiations for a postwar peace treaty with Japan, deemed as an apparent reaction to Japan's sanctions against Moscow for invading Ukraine, prompting Tokyo to protest the move Tuesday.

Russia also announced Monday that it was halting a visa-free program that allows former Japanese residents to periodically visit the Russian-controlled, Japan-claimed islands off Hokkaido, while indicating that it will withdraw from joint economic activities on the disputed islands.

Photo taken Jan. 30, 2019, from a Kyodo News airplane shows Russian-held, Japanese-claimed islands off Japan's northernmost main island of Hokkaido. At the bottom is Cape Nosappu in Hokkaido, and in the center is the Habomai islet group. (Kyodo) ==Kyodo

While the ministry said Japan's anti-Russia actions are to be blamed for the deterioration of bilateral relations, Tokyo rebutted the claim, saying it is wrong for Moscow to translate the consequences of its invasion of Ukraine into Japan-Russia relations.

"Russia's actions are extremely unreasonable and totally unacceptable," Prime Minister Fumio Kishida told a Diet committee session, noting "all the current situations have originated from Russia's aggression on Ukraine."

Japan's Vice Foreign Minister Takeo Mori summoned Russian Ambassador to Japan Mikhail Galuzin to the Foreign Ministry in Tokyo to protest Russia's announcement.

Mori told the envoy that Russia cannot justify the invasion of Ukraine as it is a violation of international law, and it is natural for Japan to impose powerful sanctions, the Japanese ministry said.

Japanese Prime Minister Fumio Kishida speaks at a House of Councillors Budget Committee session in Tokyo on March 22, 2022, wearing a mask for protection against the coronavirus. (Kyodo) ==Kyodo

The protest came after Russia's Foreign Ministry said in a statement that the suspension of the peace treaty negotiations stems from Japan's unilateral and unfriendly restrictions on relations over the Ukraine situation.

"Under these circumstances, it is impossible to hold discussions on signing of a document which is important to both countries," the statement said.

Kishida, however, said Japan's stance to seek the settlement of the territorial issue and conclusion of a peace treaty with Russia "remains unchanged."

Joining the international move to punish Russia, Tokyo has already unveiled a series of sanctions against Moscow including stripping the country of its "most-favored nation" trade status and freezing assets owned by Russian President Vladimir Putin.

Japan claims the Soviet Union illegally seized the four islands -- Kunashiri, Etorofu, Shikotan and the Habomai group of islets -- soon after Japan's surrender in World War II in August 1945, while Moscow argues the move was legitimate.

During a 2018 summit between then Japanese Prime Minister Shinzo Abe and Putin, the two countries reaffirmed they would carry out peace treaty talks based on a 1956 joint declaration, which states the two smaller islands of Shikotan and the Habomai islet group will be handed over to Japan following the conclusion of a peace treaty.

In July 2020, however, Russia's amended Constitution took effect, with a provision barring Moscow from transferring any of its territory.

The development means that Russia is unlikely to make a compromise with Japan regarding the disputed islands. The decades-long territorial row has prevented the two countries from concluding a peace treaty.

After Russia started a military attack on Ukraine on Feb. 24, Japan joined forces with other Group of Seven industrialized countries in slapping Moscow with severe economic sanctions.

Kishida, who plans to attend a G-7 summit meeting on Thursday in Brussels, told reporters that it is important to share Russia's move to break off bilateral peace treaty talks with Japan as "an example of what is happening in Asia."

While Japan's government under Abe had avoided describing the four islands as an integral part of Japanese territory in an apparent effort not to impact the peace treaty talks with Russia, Kishida used the phrase at a parliament debate on March 7 following the launch of Russia's invasion of Ukraine.

Kishida has taken a stance of prioritizing the return of the four islands to Japan in peace treaty talks with Russia, but negotiations have shown little progress.

"The bilateral relations' return to normal is nowhere in sight as long as Putin stays on as president," one Japanese government source said.

The four islands are called the Northern Territories by Japan and the Southern Kurils by Russia.