TOKYO, Nov 21 (Reuters) - The yen rose sharply on Friday after Japanese Finance Minister Taro Aso said the currency's weakening over the past week has been too fast and that rapid currency moves are unwelcome, whether they are up or down.

The dollar fell to as low as 117.45 yen from around 118 yen .

(Reporting by Hideyuki Sano; Editing by Paul Tait)