The China Harbour Engineering Company said in a statement late Monday that the contract, signed in Khartoum on February 1, was worth 900 million euros (1.2 billion dollars).

The project, which covers the construction of the new airport's runway, airline terminals, control towers and other key facilities, will replace Khartoum's existing airport located in the centre of the capital.

"Upon completion, the new airport will greatly upgrade (the) internationalisation of Khartoum," said the firm, a subsidiary of the majority state-owned contracting giant China Communications Construction Company.

China, a key supporter of Khartoum and top buyer of Sudan's oil, has invested heavily in its infrastructure and oil industry, filling a gap left by the exit of Western firms after US sanctions linked to the Darfur conflict.

State-run China National Petroleum Corporation operates three of Sudan's four oil producing consortia and built the oil refinery in Khartoum as well as the two pipelines that pump crude to Sudan's export terminal in Port Sudan.