Mr Hu made the call at the seventh plenary session of the Central Commission for Discipline Inspection, the party's top anti-graft watchdog, a three-day meeting which ends today.

He said the party still faced an 'arduous fight against corruption', and the focus should be upon 'major and high-level corruption cases' and the stern punishment of corrupt officials.

Unlike previous anti-graft statements, Mr Hu's speech yesterday seemed to focus on corruption among high-level officials and appeared to signal Beijing's intention to intensify a campaign that has already brought down a number of senior central government and local officials.

The campaign, launched in June, has led to the downfall of several high-ranking officials, including Shanghai party chief Chen Liangyu , Beijing vice-mayor Liu Zhihua , top statistician Qiu Xiaohua and Qingdao party chief Du Shicheng .

Mr Hu said yesterday it was a major 'political task' to promote ethical behaviour among senior party officials, urging the party to take painstaking efforts to improve the education, supervision and self-discipline of leading cadres.

Apparently referring to the decadent lifestyles of many officials, Mr Hu urged cadres to pursue 'wholesome lifestyles, healthy hobbies and strictly adhere to moral principles'. Most corrupt party officials arrested last year were accused of 'loose morals', a euphemism referring to keeping mistresses.

Analysts say Mr Hu's anti-corruption campaign also has the benefit of being fused with his political agenda to consolidate power in the run-up to the 17th party congress this autumn, when a major leadership reshuffle is expected.

As a further sign of his intensified political manoeuvring ahead of the congress, Mr Hu called for 'an involuntary respect for central authority' and 'a unified thought' in executing the central government's policies and guidelines.

Joseph Cheng, of City University of Hong Kong's Department of Public and Social Administration, said Mr Hu was sending a powerful message to provincial and city leaders - who, with their develop-at-all-costs mentality, have been the main culprits found by the anti-corruption drive - that they had better pay closer attention to Beijing's policy line.

Mr Hu was set to emerge with more political capital from the corruption crackdown, Professor Cheng said. '[It] is a tactic that Mr Hu is using to secure key positions in the 17th party congress.'

Hong Kong-based political scientist Linda Li said it would be in the Communist Party's best interests to decouple the fight against corruption and power politics.

'People will say it's not a real fight against corruption, it's all politics; and they will become more cynical about communist rule.'