"We want to paint a clearer picture of the three petroleum groups in Thailand - PTT, Esso and Chevron. We don't want to create a perception that the refining industry has been dominated by PTT," its president Prasert Bunsumpun said yesterday.

Three options for Star Petroleum Refining have been proposed. First, Star Petroleum would seek a listing on the exchange and PTT would sell its stake to the general public. Second, PTT's stake would be offered directly to Chevron. Third, PTT would swap its stake for a share of Chevron's upstream petroleum business overseas.

Prasert said Star Petroleum shares should not be priced lower than Rayong Refinery's book value. As of Monday, Rayong Refinery's book value was Bt16.19.

PTT's refining business also owns 49.54 per cent of Thai Oil, 48.75 per cent of Rayong Refinery and 29.75 per cent of Bangchak Petroleum.

As refining margins float up along with crude oil prices, PTT has come under pressure to help consumers by holding off hiking its retail oil prices as long as possible.

However, other retailers complain that they are suffering as PTT uses its refining profits to subsidise its distribution business. Such a practice is prohibited in some countries and their retail oil business shows huge losses due to low marketing margins, they said.

Prasert said the retail oil industry remained competitive, as PTT's share is only 34 per cent of total volume and 10 per cent of the 18,000 stations nationwide.

"Other retailers could be affected by PTT's actions on oil prices, but it's up to each company's policy. In operating the business, PTT needs to take into account the best interests of all parties - consumers, the general public and the entire economy," he said.

In one or two days, PTT could slash retail oil prices if global crude prices fall, thus telling consumers that oil prices can go both up and down. Although crude oil prices have eased to US$66 (Bt2,283) a barrel, finished oil prices remain high at $88 a barrel for petrol and $82 for diesel, he added.