BEIJING China learnt an "extremely profound" lesson from the Bo Xilai scandal and will make fighting corruption a priority alongside further reform, a Communist Party spokesman said on Wednesday, a day before a key congress opens to usher in a leadership change.
But Cai Mingzhao said political reform had to be realistic, and that China's current system of one-party rule was not up for debate.
Bo, once a contender for top leadership in the world's second-largest economy, was ousted in China's biggest political scandal in two decades earlier this year following a scandal in which his wife murdered a British businessman.
"Our country is a society in transition, the phenomenon of corruption happens easily and often and is a long-term and arduous task for the party (to tackle)," Cai told a news conference in Beijing's cavernous Great Hall of the People.
"The issues of Bo Xilai and Liu Zhijun ... occurred at senior levels within the party and are serious corruption cases; the lessons (learnt) were extremely profound," Cai said, referring also to a railways minister sacked for graft last year.
Bo's wife, Gu Kailai, and his former police chief, Wang Lijun, have both been jailed over the scandal that stemmed from the murder of British businessman Neil Heywood while Bo was party chief of the southwestern city of Chongqing.
The government has accused Bo of corruption and of bending the law to hush up the murder. Prosecutors formally began a criminal probe into Bo last month.
The drama over Bo's case has overshadowed what was supposed to be a carefully choreographed five-yearly congress, at which President Hu Jintao will give up his position as party chief to anointed successor Vice President Xi Jinping.
Xi, however, faces more than just the Bo crisis.
Advocates of reform are pressing Xi to cut back the privileges of state-owned firms, make it easier for rural migrants to settle in cities, fix a fiscal system that encourages local governments to live off land expropriations and, above all, tether the powers of a state that they say risks suffocating growth and fanning discontent.
Cai said that reform was a vital path for China to take, but stopped short of providing any details.
"As we go forward in our reforms in the future we will ... stress more the importance of putting people first," he told reporters.
While Cai said there would be greater efforts at promoting "inner-party democracy" - in other words, encouraging greater debate within the party - there would be nothing to suggest the party was willing to relax its grip on power.
"The leading position of the Communist Party in China is a decision made by history and by the people," he said. "Political system reform must suit China's national reality. We have to unswervingly stick to the right path blazed by the party."
(Additional reporting by Ben Blanchard and Sui-Lee Wee; Writing by Nick Macfie)