But analysts said the debate on the amendments had highlighted sharp differences within the party on its status in relation to the constitution.

The revision, the fourth since the constitution was promulgated in 1982, has been shrouded in secrecy. The process was started last June by NPC chairman Wu Bangguo, but the debate proved so controversial the party barred public discussion.

A draft of the changes was passed by the NPC legal committee in October and a summary of the revision released to the public in December.

There was little disagreement on the changes, including that the theory of the Three Represents should be added to Marxism, Leninism, Mao Zedong Thought and the Deng Xiaoping Theory in the preamble to the constitution to assert the party's legitimacy. The theory of the Three Represents holds that the party represents the interests of advanced culture, advanced productive forces - including private entrepreneurs - and the broad masses.

What has proved contentious is whether the party should submit itself to the constitution as the nation moves towards rule of law by protecting human rights and private property.

The debate epitomises both the promise and limitations of the leadership of President Hu Jintao and Premier Wen Jiabao. When Mr Hu made his first public appearance after becoming party general secretary in October 2002, he chose to speak on the 20th anniversary of the 1982 constitution. The timing of the speech sparked hopes that the rule of law would be the hallmark of the new leadership.

But hardliners closely linked to the General Office of the Central Committee are pushing to maintain the party's supremacy. They argue that the party holds a unique position in uniting the nation.

This camp is headed by Politburo Standing Committee members Zeng Qinghong, Wu Bangguo and Li Changchun. They have used the party's vast organisation to draw senior and middle-ranking cadres to their cause.

In their eyes, yielding power to the constitution would weaken the party. Without a strong party to guide the nation, the country could disintegrate, they argue. They acknowledge that some party members have abused their power but believe corruption should be dealt with internally.

The other camp, which includes President Hu and Premier Wen, believes the rule of law is the right path for the party. They say it has strayed from its goal of building a socialist democracy and working in the people's interest, the original goals that have fallen by the wayside because of the party's chequered history since 1949.

The idea that the party should uphold the rule of law did not start with Mr Hu and Mr Wen. Several third generation leaders, including Wan Li , Qiao Shi and Li Ruihuan, had championed the cause, a party veteran said.

The debate spilled over into the pages of the party mouthpiece, the People's Daily, in December.

Fang Li, deputy director of policy studies of the party's Central Committee, wrote that the revision should strengthen and improve the party in its leadership and resist the erosion of Marxism.

The next day, Xin Chunying, a member of the NPC's legal committee, wrote that the government, the armed forces, political parties and all social groups must abide by the constitution and laws. Legal experts have been ordered not to comment on the revision.

Cao Siyuan, a leading constitutional scholar, came under surveillance and harassment and was recently spirited out of the country, said a source close to him. He is expected to return after the NPC session.

Liu Xiaobo, a leading liberal thinker and pro-democracy activist, said the nation would take a giant step by upgrading the protection of private property and honouring human rights in the constitution.

'China will abandon its earlier insistence on defining human rights as the right to subsistence,' he said. 'Without qualifying human rights as being 'with Chinese characteristics', China is embracing them as a set of universal values.'