The mainland's two biggest telecommunications service providers, China Mobile and China Telecom Corp, plan to step up key investments despite the challenges posed by the lingering economic crisis. China Mobile, the world's largest wireless network operator, with 508.4 million subscribers as of last month, reported yesterday a 1.8 per cent rise in net profit to 83.9 billion yuan (HK$95.24 billion) for the nine months to September from a year earlier. The growth was achieved through lower mobile call charges, higher handset subsidies and intensified marketing, which helped generate 51.12 million additional customers during the period. Revenue rose 8.9 per cent year on year to 327 billion yuan. Chairman and chief executive Wang Jianzhou (above) said there were signs of slower customer growth because of economic uncertainty and greater domestic competition, but the operator was determined to 'adapt rapidly to changes in the business environment'. That is why, he said, the company 'will continue to increase its investments in sales channels, customer service, network optimisation, support system and research and development'. Fixed-line network giant China Telecom, which had 194.4 million telephone, data, broadband and leased lines in service as of last month, posted a 33.9 per cent fall in net profit for the first three quarters of the year to 11.4 billion yuan. The carrier acknowledged the impact of the economic slowdown and strong competition on its business but primarily blamed the loss on an increase in spending to market its mobile-telephone services, coupled with the loss of fixed-line subscribers. However, revenue rose 15.3 per cent year on year to 154.8 billion yuan thanks to growth in its internet and data services and development of its mobile business. Chairman and chief executive Wang Xiaochu said China Telecom would sharpen its focus on developing its integrated fixed and wireless services and the progressive rollout of its 3G services. Analyst Steven Liu of DBS Vickers Securities said: 'China Mobile's results were in line with expectations, but China Telecom's were slightly below.' He expected a pick-up in business for both operators in the fourth quarter as the economy further improves. A government revamp of the mainland's telecommunications sector has repositioned China Mobile, China Telecom and China Unicom as integrated fixed and wireless network operators.