TOKYO (Reuters) - An official of Japan's finance ministry said on Wednesday that it was closely watching the currency market to see if any speculative factors are behind market moves.

The official declined to comment on currency levels.

He was speaking to reporters shortly after the dollar fell to a low of 100.40 yen <JPY=> due to risk aversion.

(Reporting by Takaya Yamaguchi; Writing by Tetsushi Kajimoto; Editing by Richard Borsuk)