SINGAPORE - The chairman of palm oil giant Wilmar International and one of the company's shareholders have joined the ranks of Singapore billionaires, Forbes said Thursday.

The addition of Kuok Khoon Hong and Peter Lim brings to seven the number of billionaires in the city-state, according to a list published by Forbes Asia magazine.

Kuok, 59, is the chairman and chief executive officer of Wilmar International while Lim is a shareholder in the firm, Forbes said in a statement.

It said Kuok, nephew of Malaysian tycoon Robert Kuok, has a net worth of 1.3 billion US dollars.

Lim, 55, son of a fishmonger, provided seed money to Wilmar and is worth 1.1 billion dollars, Forbes said.

Property magnate Ng Teng Fong, 80, and his family remained Singapore's richest, worth seven billion dollars, it said.

The family control the privately-owned Far East Organisation and have a 72 percent stake in Hong Kong-listed Tsim Sha Tsui Properties, it added.

The Khoo family stayed Singapore's second-richest, with net worth of 6.1 billion dollars, the magazine said.

In 2006 the family sold the stake held in Britain's Standard Chartered Bank by their late father, Khoo Teck Puat. They still control the Goodwood Group of Hotels, Forbes said.

Banker Wee Cho Yaw and his family held on to third position, worth 3.6 billion dollars. Wee is the chairman of United Overseas Bank.

Forbes said the combined net worth of Singapore's 40 richest people was unchanged at 32 billion dollars in the annual ranking.

Aside from its local population of rich people, tiny Singapore is fast gaining a reputation as the Switzerland of Asia for the world's growing ranks of multi-millionaires.

Banks have beefed up their wealth management services to deal with the ultra-rich looking to invest their millions.