Japan is to ban exports of luxury goods to Russia in order to put pressure on oligarchs -- wealthy business tycoons thought to be close to President Vladimir Putin.

The list covers 19 items, including cars worth more than 6 million yen, or about 48,000 dollars and motorcycles worth more than 600,000 yen, about 4,800 dollars. It also encompasses pianos worth more than 200,000 yen, some 1,600 dollars, natural pearls, high-end Japanese whiskey and watches with a value exceeding 40,000 yen, or about 300 dollars. The export ban goes into effect April 5.

Japan already bans exports of about 300 items to Russia, such as those that can be converted to military use and general-use semiconductor chips. Items to be used for humanitarian purposes are exempt.

Japanese trade minister Hagiuda Koichi told reporters on Tuesday that the country will keep a close eye on the situation in Ukraine and draw up further sanctions in cooperation with the international community.