South Africa's largest healthcare insurer, Discovery Holdings Ltd, is to increase its stake to 25 percent in Ping An Health Insurance Co, a unit of China's second-biggest life insurer by premiums after China Life.

The parent company, Ping An Insurance (Group) Co of China Ltd, and Discovery have agreed for the South African insurer to increase its stake in Ping An's health insurance unit to 24.99 percent from 20 percent, a Ping An statement said on Friday. Discovery acquired its initial stake in Ping An Health Insurance Co in 2010.

Ping An did not disclose pricing, and was not available for comment on Friday. The transaction is likely to be finalized by the second quarter of next year, according to The Wall Street Journal.

Analysts said they expect the latest purchase to precede closer cooperation by the two companies, giving the South African insurer a firmer foothold in the expanding Chinese market.

"I would not say it is a large-scale purchase, as it is an increase in holding of the subsidiary company. It may have to do with both sides' cooperation to develop new business," said Zhang Qi, an analyst with Haitong Securities.

Ping An said in a statement there could be future cooperation between the two companies in China's insurance market.

Ping An stocks closed lower on Friday, with its A shares down 1.67 percent and H shares down 0.77 percent.

"Ping An and Discovery share the same vision, that we want to fundamentally change the market operation and provide creative, and security-rich products to the consumers," said Adrian Gore, chief executive officer of Discovery.

Thailand-based Charoen Pokphand Group (CP Group) received approval to buy HSBC's 15.57 percent stake in Ping An Insurance Co, replacing it as the insurer's largest stock holder earlier this month.

China's population of more than 1.35 billion and the authorities' determination to push forward healthcare reform has attracted a steady stream of foreign insurers and banks to the country.

Ping An Health Insurance provides health insurance, reinsurance and consultancy services in China. The unit is based in Shanghai, with a registered capital of 625 million yuan ($100.8 million), according to Ping An's website.

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