UOB Kay Hian Securities strategist Kitpon Pripisankit added that OR would be listed on the SET50 and SET100 Indices on February 17 and the MSCI Global Standard Index on February 26.

"Therefore, we expect OR's share price to rise higher than brokerage firms' expectations of between Bt19 and Bt24 per share," he said.

He added that OR's fair price is between Bt25.3 and Bt31.3 per share based on the company's oil and retail business value.

The price of OR shares at 10.54am on Monday hit the highest level at Bt36.50 per share, up Bt6 or 20.51 per cent, due to mass buy-ups of its shares.

Bright short-term outlook for PTT Oil and Retail shares

The price of PTT Oil and Retail Business (OR) shares is expected to rise further in the short term after its market capitalisation exceeded Bt330 billion, an expert said.