MOSCOW (Kyodo) Foreign Minister Nobutaka Machimura has sent a letter to Russian Industry and Energy Minister Viktor Khristenko asking for the appropriate handling of huge back tax cases involving Japanese firms in the country, the Japanese ambassador to Russia said Tuesday.

Among the cases, Russian tax authorities have reportedly imposed back taxes of 420 million rubles (about $15 million) on a local production unit of the Japan Tobacco group for alleged tax evasion in 2001.

That bill came after Japan Tobacco Inc.'s sales unit in Russia, JTI Marketing and Sales, was charged 2.4 billion rubles last fall for alleged tax evasion in 2000. The case is in the courts.

As the Russian unit of the JT group, based in St. Petersburg, is one of the largest investments by Japanese firms in the country, the back taxes may have adverse effects on future investment in Russia.

The Japanese government, therefore, has decided to take the unusual step of intervening in the problem, according to Ambassador Issei Nomura.

Tokyo also plans to raise the issue at a Japan-Russia intergovernmental trade and economic meeting on April 22 to be cochaired by Machimura and Khristenko, Nomura said.