A South Korean foundation recently launched to support former "comfort women" has asked the Japanese government for Prime Minister Shinzo Abe to write a "letter of apology" to the victims, a foundation official said.

Japan late last month disbursed ¥1 billion to the Reconciliation and Healing Foundation under a landmark bilateral deal struck last December over the women who were forced into wartime brothels for the Japanese military.

The foundation, which is to pay about ¥10 million to each surviving woman and ¥2 million to surviving families, hopes to boost support for the agreement by including the letter with the payment, so that more women opt to receive it. But there are fears that the request for the letter not mentioned in the December agreement may add to distrust of Seoul by Tokyo.