TOKYO (Reuters) - Nomura Holdings Inc <8604.T> Chief Executive Kenichi Watanabe will resign to take responsibility for leaks on planned share offerings at the company's brokerage unit, sources said on Thursday.

Chief Operating Officer Takumi Shibata will also resign in response to the scandal, Kyodo News Agency said.

Nomura, due to report results on Thursday, has confirmed it was the source of leaks on planned share offerings by energy firm Inpex <1605.T>, Mizuho Financial Group <8411.T> and Tokyo Electric Power <9501.T> in 2010. The scandal has already cost it clients.

(Reporting by Emi Emoto, Writing by Mayumi Negishi; Editing by Chang-Ran Kim)