Japan Post Holdings Co. named Masatsugu Nagato as president of the recently listed mail and financial services giant, replacing Taizo Nishimuro following his hospitalization last month.

Nagato, 67, will take the post on April 1, the Tokyo-based company said Wednesday.

He joined the group as president of its banking unit last year after previously serving as chairman of Citibank Japan Ltd. Nishimuro, 80, will remain a board member.

Nagato will take the reins of a company that faces challenges to profitability as mail volumes fall and the Bank of Japan's negative interest rates policy threatens to curtail investment returns for its bank and insurance units.

At a news conference later in the day, Nagato said the postal and financial giant will seek growth through mergers and acquisitions, as the group is suffering from falling interest rates amid the Bank of Japan's negative rate policy.

He also said the state-backed group aims to strengthen sales of investment trusts and insurance products while also looking to increase investment in overseas stocks.

Nishimuro oversaw the postal group's three-pronged initial public offering last year, a ¥135.6 billion ($12 billion) deal that attracted mostly individual investors and was the nation's biggest privatization this century.

His health is unlikely to improve in the near future, but he is fit to perform his duties as a board member, Vice President Yasuo Suzuki said at a news briefing in Tokyo, without disclosing the former president's condition.

Nishimuro said in November that he plans to decide on a successor around June or July 2017, in time for the company's annual shareholders meeting. He is a former chief executive officer of Toshiba Corp. and Tokyo Stock Exchange Inc.