TOKYO, Jan 16 (Reuters) - Fast Retailing said on Tuesday its Uniqlo unit filed a lawsuit in Japan against the operators of Shein, claiming the Chinese fashion company copied its round mini shoulder bag.

The petition was filed on Dec. 28 in the Tokyo District Court against Roadget Business Pte, Fashion Choice Pte, and SHEIN JAPAN, Fast Retailing said in a statement. (Reporting by Rocky Swift; Editing by Jacqueline Wong)