PCCW, Hong Kong's biggest telephone company, will raise its charge for connecting calls between fixed-line and mobile-phone users by 25 per cent from next month. PCCW will increase the interconnection charge to 5.45 HK cents per minute from 4.36 HK cents, according to the Office of the Telecommunications Authority, the industry regulator. 'This revision to the charge is a business decision,' according to a spokesman at PCCW. Interconnection fees are paid by mobile carriers when their users make calls to a fixed-line phone. PCCW runs both services. 'The fierce competition will render mobile operators unable to transfer the extra cost to end-users,' a telecommunications analyst said. A SmarTone spokesman said PCCW's new charge was 'definitely unfair' to mobile operators. 'We will try to deal with it through a commercial arrangement. If that fails, we will seek the Ofta determination to settle the price dispute,' according to the spokesman. Hutchison Telecom (Hong Kong) declined to comment because it was studying the issue. CSL New World Mobility, the city's biggest mobile operator with over 2.6 million subscribers, said they would respond to PCCW's move on Monday. Tarek Robiatti, chief executive of CSL New World Mobility, said earlier in an interview that the interconnection regime was totally unfair and did not exist in other developed markets.