SINGAPORE, June 11 (Reuters) - Shares of Olam International Ltd surged 8 percent to the highest in nearly three weeks after the commodities firm announced a share buyback program, a move which analysts said signalled the management's confidence in the company's outlook.

"The whole market is up today and all the high-beta stocks are rallying," said Lee Wen Ching, an analyst at CIMB Research. "But the management's move to introduce a share buyback program is a very strong signal that they believe the valuations are cheap and they remain confident in the group's long-term prospects."

Olam shares rose as much as 8 percent to S$1.755, the highest since May 23, while the broader Straits Times Index gained 1.8 percent. Olam topped index gainers.

Olam shares took a beating in the last few weeks, along with other commodity-related stocks, on concerns about the impact of a slowing global economy. The shares were down 24 percent so far this year as of Friday's close versus a 3.5 percent rise in the market.

Olam may buy up to 10.0 percent of its total number of issued shares, or up to 244,230,986 shares, at a maximum price of 105 percent of the average closing price of the last five market days at the time of acquisition, the company said in a statement late on Friday. (Reporting by Eveline Danubrata; Editing by Anshuman Daga)