LUSAKA (Reuters) - Zambia plans to spend $385 million to modernise the capital city's main airport and turn Lusaka into a regional aviation hub, president Michael Sata said on Thursday. Sata said in a statement the government would redesign Kenneth Kaunda International Airport to handle 4 million passengers a year, double its current capacity, and had so far released $25 million for the project. Zambia was at the centre of two regional growing markets and therefore offered immense opportunities for both local and foreign investors, he said. The Southern African Development Community had about 277 million people and a GDP of $575.5 billion while the Common Market for Eastern and Southern Africa had a population of roughly 459 million people and GDP of $508 billion, he said. "In this vein, Lusaka which is about 2 hours away from most sub-regional capitals by air, is therefore ideal to be regional hub for passengers and cargo," Sata said. Africa's top copper producer was also sourcing for $522 million to build a new airport in the mineral-rich copperbelt province, about 330 km from Lusaka, he said. The $40 million refurbishment of another airport in Livingstone, the tourist capital about 460 km from Lusaka, was almost complete and the improved airport would become fully operational in April, he said. The investment in infrastructure was expected to boost Zambia's agriculture, manufacturing and tourism sectors, he said. Zambia would intensify efforts to attract investment in the development of airport infrastructure including terminals, cargo infrastructure, hotel and auxiliary infrastructure across the country, he said.