Mainland carriers will increase fuel surcharges by 33 per cent on long-haul international flights from June 1, as rising jet fuel prices dent profits. Beijing regulates fuel surcharges on domestic routes, but not on international ones. Airlines can adjust the fee in response to changes by rivals. Air China said yesterday it would increase its fuel surcharge on round trips to 1,600 yuan (HK$1,800) from 1,200 yuan on United States, Europe, Middle East and Australian routes after its rivals, China Southern Airlines and Hainan Airlines, unveiled similar plans at the weekend. However, no unified increase in surcharges will be imposed on Asia-Pacific routes by the airlines. 'The change will be route by route [in Asia] and the adjustment will be very little,' Air China board secretary Huang Bin said yesterday. Competition on Asian routes was so fierce that mainland carriers could not raise fuel surcharges, said Martin Wong, a transport analyst for Guotai Junan Securities. China Eastern Airlines Corp said yesterday its new fees would be announced today. There is an unwritten rule that leading mainland airlines impose the same fuel surcharges on similar routes. 'The increase in fees can help offset half of the increase in international fuel costs as the new surcharges become effective in the second half,' Mr Wong said. He said international jet fuel prices would surge 34 per cent to 7,500 yuan per tonne on average this year, up from 5,600 yuan last year. Jet fuel accounts for more than 40 per cent of the operating costs of mainland carriers. However, the rise in surcharges may not help the airlines attain profitability on international routes because of the low percentage - or passenger load factor - of seats sold. China Eastern recorded a 58.4 per cent load factor in the first four months, while China Southern filled 65.6 per cent of its seats on international legs. Air China, the most profitable mainland airline, sold 74.8 per cent of its seats on international routes in the period. The international average is more than 77 per cent. Meanwhile, Cathay Pacific Airways will raise its ticket surcharges by 37 per cent, the biggest increase since 2004, a Bloomberg report said. Short-haul levies would climb to HK$171 each way from HK$125 and long-haul surcharges would jump to HK$710 from HK$518 from June 1, Civil Aviation Department spokesman Francis Ma said.