Japan Post Holdings Co., with $30 billion' worth of properties across the nation, will redevelop sites in central Tokyo, Osaka and Nagoya as it turns to real estate as a new source of profit, a company official said.

The former state-run mail service that was privatized by the government last year will spend about ¥300 billion redeveloping the central post office sites in the country's three biggest cities into office buildings, said Takashi Saito, deputy senior general manager of Japan Post Holdings Co.

"Since we own the land already, we don't face risks related to potential losses by holding on to assets, unlike others," Saito said in an Oct. 21 interview.