TOKYO - A month after the detention of a Japanese journalist in Russia for alleged spying, no clear progress has been seen in securing his release with Moscow seen taking a tougher stance on Japan amid already strained bilateral ties following its full-scale invasion of Ukraine.

The Japanese government has continued to call for the release of Hokkaido Shimbun newspaper reporter Yuki Imai, who was arrested Oct. 13 in the Sakhalin region in the Russian Far East and taken to a detention center in Moscow. Concerns linger that an early release may be difficult.

"Japan has requested Russia at various levels to immediately release the national, to extend humanitarian considerations and to provide fair and impartial treatment," Japanese Foreign Minister Toshimitsu Motegi said Friday.

Chief Cabinet Secretary Minoru Kihara stressed the previous day that while pushing for his release, the Japanese government will continue to impose sanctions on Russia, calling its invasion of Ukraine since 2022 "an act that shakes the international order."

Russia's Federal Security Service, which is investigating the case, has not issued any official statements since announcing Imai's detention on the day it happened. His detention period is set to expire on Dec. 12 but could be extended.

The incident is seen as part of Russian President Vladimir Putin's hostage-taking diplomacy seeking to win concessions from Japan on political issues. The detention has raised concerns that Russia could use the journalist as leverage to pressure Japan to halt its support for Ukraine or lift its sanctions on Moscow.

Some observers have speculated that Russia held the journalist to retaliate against Japan's handover to Germany of a Russian national suspected of being a key member of ransomware group Qilin, which is believed to be behind a 2025 cyberattack on a major Japanese beverage maker.

In many cases, people charged with spying by the FSB are tried behind closed doors and sentenced to lengthy prison terms.

In a similar case, U.S. journalist Evan Gershkovich was detained on espionage charges by the FSB while reporting on Russia's invasion of Ukraine in Yekaterinburg, a city in central Russia, in March 2023.

While the U.S. government declared the reporter of The Wall Street Journal "wrongfully detained" in April 2023, he was sentenced to 16 years in a high-security penal colony. In August 2024, he was released as part of a major multinational prisoner swap.

The FSB claims the Japanese reporter gathered information about mobilized troops and volunteers participating in its military operation against Ukraine under instructions from Japanese intelligence.

Japanese Prime Minister Sanae Takaichi has denied that the government is engaged in espionage in Russia, while Hokkaido Shimbun said Imai was conducting "ordinary news gathering" and that the newspaper does "not conduct reporting or gather information based on government directions."

At the end of October, Motegi called for Imai's immediate release during talks with his Russian counterpart Sergey Lavrov, their first formal meeting in about five years, on the sidelines of a Group of 20 gathering in the United States.

According to the Russian Foreign Ministry, Lavrov stressed in the meeting that Japan needs to abandon its "unfriendly policy" toward Russia if a full-scale dialogue is to resume.

Pressure on Japan also increased with Putin recently moving to effectively seize Russian operations of cigarette giant Japan Tobacco Inc. citing its assets belonging to "individuals from unfriendly countries."

A senior Japanese government official said, "Options of easing sanctions or pulling back support for Ukraine should not be on the table." But the Japanese government is expected to look for chances of dialogue with Russia.

Takaichi and Putin are both expected to attend next week's Asia-Pacific Economic Cooperation forum summit in the southern Chinese city of Shenzhen.

Japan and Russia have long been locked in a territorial dispute over a group of islands off Hokkaido, called the Northern Territories in Japan and the Southern Kurils in Russia.

The dispute has kept the countries from signing a peace treaty after World War II. Russia has controlled the islands since Soviet forces occupied them after Japan's surrender in the war in 1945.

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