(Reuters) - Office Depot Inc <ODP.O> said on Monday Chief Executive Roland Smith would retire, three months after the second-largest U.S. office supplies retailer and bigger rival Staples Inc <SPLS.O> abandoned their planned merger.

Smith would continue as CEO until a replacement was found, which the company expected by the end of the first quarter of 2017.

Smith, 62, was appointed to the top job in November 2013.

The company also said it would consolidate its retail, contract, ecommerce and marketing operations under a newly created role of chief operating officer, North America.

Troy Rice, who led the integration of the Office Depot and OfficeMax store operations, was named the COO.

The office supplies retailer also appointed Rob Koch to the newly created position of executive vice president, business development, to identify new business opportunities.

Koch, currently senior vice president for real estate, will continue to oversee the company's real estate portfolio, Office Depot said.

Office Depot said earlier this month it would shut 300 more stores in the next three years in addition to the 400 stores it had already closed.

The company's sales have declined for seven straight quarters amid strong competition from online giant Amazon.com Inc <AMZN.O>.

Office Depot's merger with Staples was thwarted in May by antitrust regulators.

Since then, the company's shares had lost 42 percent of their value to Friday's close. They were up 1.42 percent at $3.57 in morning trading on Monday.

Staples Chief Executive Ron Sargent stepped down in June.

(Reporting by Abhijith Ganapavaram and Subrat Patnaik in Bengaluru; Editing by Anil D'Silva and Sriraj Kalluvila)