Fosun International Ltd, China's biggest private conglomerate, has bought a controlling stake in Portugal's largest insurance group for 1 billion euros ($1.36 billion), in a bid to build an investment group focused on the insurance sector.

Fosun International's chairman Guo Guangchang said in statement on Thursday that the Hong Kong-listed company outbid US investment fund Apollo Global Management LLC to acquire an 80 percent stake in state-owned Caixa Seguros e Saude SGPS SA, Portugal's largest insurance group, which is owned by state bank Caixa Geral de Depositos SA.

Fosun won the bid for the acquisition of 80 percent of the share capital and voting rights of Fidelidade SA, 80 percent of the share capital and voting rights of Multicare SA, and 80 percent of the share capital and voting rights of Cares SA, all fully owned units of Caixa Seguros e Saude, the statement said.

Wang Qunbin, Fosun Group's president, led the team that finalized the deal.

The team was originally looking for M&A targets in neighboring Spain, but a local adviser told them to look into Portuguese assets instead, an insider close to the Chinese company said.

Fosun could not be reached for comment.

The deal brings Fosun a step closer to building an investment conglomerate with its core business based on insurance, industry observers said.

In 2012, Fosun and the US-based Prudential Financial Inc established Pramerica Fosun Life Insurance Co Ltd, a 50-50 joint venture, which has its headquarters in Shanghai.

In January last year, Fosun invested $468 million to get an 85 percent stake in reinsurance firm Peak Reinsurance Co Ltd in partnership with International Financial Corp, a member of the World Bank Group. This investment had generated millions of US dollars in profit by the end of last year, the Economic Observer recently reported.

Liang Xinjun, chief executive officer of the Fosun Group, told China Daily earlier that insurance deals will help the company to reach its objective of becoming a world-class investment company.

The latest acquisition is also in line with Fosun's expansion strategy, which focus on global investments, said Alan Gao, a vice-president and senior analyst at Moody's Investors Service.

"There are uncertainties associated with the company's plan to operate and integrate the Portuguese insurance business, given that it lacks a track record in the European market," said Gao.

According to a Moody's rating report issued in December, Fosun's bid for Caixa Seguros e Saude is credit negative, but the outlook for the company is stable.

Fosun has not said how it will finance the acquisition in Portugal.

Fosun's liquidity is manageable given its large and liquid investment portfolio and efficient capital recycling, but its consolidated leverage remained high for the 12-month period ended June 30, 2013, the Moody's report said.

"Should Fosun take an aggressive debt-funded approach to acquisitions that compromises its liquidity management and increases its financial risk, its ratings and outlook could come under negative pressure," the report said.