Any move away from self-regulation would drive up prices at the pump Hong Kong does not need legislation to curb anti-competitive practices by oil companies and such a law would only increase costs, a large oil company claims. Yuen Ming-kwong, general manager of Caltex Companies (Greater China), said that the best solution was for oil companies to exercise self-discipline in their marketing practices. Legislative measures would only make the operation of the fuel market more complicated. Secretary for Economic Development and Labour Stephen Ip Shu-kwan said two weeks ago the need for such legislation would be assessed by the Competition Policy Advisory Group. But Mr Yuen said the introduction of additional rules and legislation would unavoidably increase operation costs. His comments came ahead of a slow-drive protest by more than 100 drivers of trucks, minibuses and other vehicles on Tsing Yi Island today. They are calling on the government to cut the duty on ultra-low-sulfur diesel and address monopoly practices in the local oil market. The protest, organised by the Joint Committee of the Transport Trade on Monitoring Fuel Prices, is scheduled to start at 10am from Container Terminal 9. Stanley Chiang Chi-wai, spokesman for the joint committee, said the Competition Policy Advisory Group should complete a review of the diesel duty rate within the next three months. The price of diesel has risen more than 20 per cent this year, hitting a peak of $7.36 a litre two weeks ago. The price now is $7.25. The government decided last month to extend the duty concession on diesel until December next year, but reiterated that there was no room for further cuts in diesel taxes. The duty, originally $2 a litre, is now $1.11. Responding to the claims of oil price-fixing, Mr Yuen said: 'As a US company, we are bound by the anti-trust law ... and we strictly prohibit our staff from discussing with our industry peers any matters related to pump prices.' He said it was a misconception that oil companies were quick to raise fuel retail prices but slow to lower them. Oil companies usually absorbed cost increases in petroleum products unless the cost rose to an extreme level, he added. Oil companies could not immediately lower the pump prices when the import costs drop because they might only have to increase them again soon after, he said. Mr Yuen said Hong Kong enjoyed the highest discount on pump prices in the world. 'Diesel users are now enjoying at least 15 per cent discount which is equivalent to around $1 per litre,' he said. But Mr Chiang said the diesel price in Hong Kong had increased by $1.29 a litre since last November compared with just 0.65 yuan in Guangdong.