June 9 (Reuters) - Russian online bank Tinkoff on Thursday said it would introduce a 1% monthly charge for accounts in dollars, euros, pounds and Swiss francs later this month in an effort to reduce its foreign currency exposure.

With their already limited cash holdings of hard currency, Russian banks have few options for investing foreign currencies because of capital controls in Russia and the risk of funds abroad being frozen as a result of Western sanctions.

Tinkoff, owned by TCS Group Holding, is already offering exchange rate incentives to encourage Russians to move FX holdings to roubles, while Raifeissen Bank International's Russian unit has already promised negative interest rates on some foreign currency holdings from June 30.

Tinkoff said the 1% service fee would be deducted monthly on accounts with a balance of over $1,000, starting from June 23.

"This measure is due to the unreliability of foreign partners in terms of foreign currency operations for Russia and is aimed at reducing Tinkoff Bank's foreign currency positions," the bank said on Telegram.

Tinkoff said it would only be possible to open savings accounts in roubles from June 23 but that it would waive the commission for transfers over the SWIFT global payments system until June 30. (Reporting by Reuters)