The European Stability Mechanism made its first short term debt auction Jan. 8, 2013, by selling 1.927 billion euros of treasury bills. Japan remains a key investor. Japanese finance minister, Taro Aso, said Japan plans to to be an active investor in the ESM bond sales. He told a news conference: "Japan will purchase some ESM bonds using its foreign exchange reserves as it monitors progress in efforts to stabilize the European situation." Japan holds $1.27 trillion in foreign exchange reserves. The move pushed the yen lower. Investors pay the ESM to keep cash for three months- the ESM treasury bills had an average yield of minus 0.0324%. The ESM fund will be used for aid to Spain's banking sector, Greece, Ireland and Portugal. Plans are for the ESM to issue three month and six month bills twice a month to reach 18.5 billion euros by the end of 1st quarter 2013. The ESM fund rating is Aa1 by Moody's Investors Service, and AAA by Fitch Ratings.