A senior official of the Xinjiang Uygur Autonomous Region says economic development and foreign trade were unaffected by riots in the border cities in February. Tourism was the sector hit by the violence, but vice-governor Li Donghui said operations of the 15 ports on Xinjiang's border were uninterrupted in February. 'Our border trade with neighbouring countries grew 15 per cent year-on-year in the first two months of this year,' he said. Xinjiang's year-on-year foreign trade grew 87.7 per cent in the first two months of this year, when exports doubled those of 1996. Foreign investment rose 48 per cent in the first two months compared with the same period last year. Xinjiang's total trade value last year was US$1.4 billion. About $170 million of that total was border trade. Mr Li said Xinjiang's border trade rose substantially last year following the central government's decision to grant a 50 per cent import-export tariff exemption to support the economic development of the mainland's remote northwestern province. The vice-governor, who is responsible for the region's economic affairs, said Beijing had promised more support to Xinjiang, including preferential policies and more funds. The central government had promised 6.5 billion yuan (about HK$6.03 billion) to fund construction of the South-Xinjiang Railway, a commitment made by economic czar Zhu Rongji when he visited the region in 1995. Construction work on the 1,500-kilometre railway started in September and will link up Korla and the west-end border city of Kashi.