Cross-border driving is due to become much smoother with the introduction later this month of an automatic toll system, which will save drivers having to pay mainland tolls with cash. The electronic toll collection (ETC) system unveiled by Chief Executive Donald Tsang Yam-kuen at the Hong Kong-Guangdong Co-operation Joint Conference on Wednesday is part of the city's effort to ease traffic flows within the Pearl River Delta. At present, drivers who have not applied for a Unitoll card on the mainland have to pay highway fees at toll booths. But after Autotoll Limited - the company which runs the automatic toll system in Hong Kong - obtains approval from Guangdong authorities this month, cross-border drivers will be able to pay tolls on 54 highways and 125 roads in Guangdong with their Hong Kong Autotoll smart card. The new card, which has already been sent to the 210,000 users of the Hong Kong Autotoll system, will cost drivers an extra HK$15 a month. Drivers who opt to pay HK$300 more for the installation of an electronic tag will enjoy automatic passage through toll booths. More than 30,000 drivers in Hong Kong own cross-border vehicle licences, but Autotoll chief executive Paul Cheng Siu-hung said at the card's launch yesterday that the number would top 100,000 if the proposed Zhuhai-Macau-Hong Kong bridge were built. 'We have invested a lot in the project, but we are optimistic our investment will pay off,' Mr Cheng said. He expects up to 50 per cent of cross-border drivers will subscribe to the service. Guangdong's vice-director for the information industry, Zou Sheng, said the toll payment system would include 175 more roads and two more highways by the end of next year. The vice-chairman of the Container Transportation Employees General Union, Tse Long, said the system would save time and money for logistics companies, but there were drawbacks. 'The new system only provides statements at the end of each month; this could delay our claim for transport fees from clients,' he said. With cash payment, cargo truck drivers receive a receipt on the spot which can be used to claim expenses.