Huang rose through the ranks of the regional Communist party in Shanghai as a protégé of Jiang Zemin, the former Chinese leader, to become the city's top official.

'Outstanding leader'

He was then promoted to the Standing Committee of the Politburo, China's highest decision-making body, in 2002 and was put in charge of economic policy matters.

His death creates an opening in China's inner circle of power ahead of a key five-yearly Communist party congress later this year, at which the current president, Hu Jintao, is expected to elevate his own supporters to key positions in the leadership.

An obituary issued by the central authorities called Huang "an excellent member of the Communist party, a long-tested and faithful Communist fighter and an outstanding leader of the party and the state," Xinhua said.

Although the health of China's leaders has long been a state secret, the government announced in March last year that Huang was ill and would not attend all official functions.

The government has never confirmed who took over Huang's job of managing China's economy following his retreat from public life.

His last public appearance was at the National People's Congress in March when he urged delegates from Shanghai to fall in behind Hu's anti-corruption drive that has seen the sacking of Chen Liangyu, a former protégé of Huang and his successor as leader of the party in the city.