Gasoline and diesel prices will go up today by a larger-than-expected 10-11%. The hike will raise the retail and ex-refinery prices of gasoline and diesel in the mainland by US$63.32 per tonne, an industry official told the the Standard of Hong Kong. Shares in Sinopec, the mainland's largest refiner, rose 4.9% on Tuesday to US$0.61 while PetroChina went up 1.8% to US$1.08. Analysts said the move may help refiners mitigate losses and regain the margins they enjoyed in the first quarter. There was some debate, however, over how the rise will affect demand, with some observers claiming the impact will be limited. The last oil price increase was in March, when China hiked up prices between 3-5% for the first time in eight months.