The public demise of Bo Xilai, the former leader of the Chinese megacity of Chongqing, had brought "great damage" to the country and the ruling Communist Party, his replacement said on Monday.

The popular Bo saw his rise through the party ranks come to an abrupt halt earlier this year. He is being probed for corruption while his wife, Gu Kailai, has been detained for suspected involvement in the murder of a British man.

The scandal, which first came to light in February and made worldwide headlines for weeks, has exposed deep divisions within the Communist Party ahead of a crucial, once-in-a-decade leadership transition, analysts say.

Bo's fall from grace began when his former right-hand man and police chief Wang Lijun fled to a nearby US consulate to seek asylum, after reportedly confronting Bo with information related to the murder of Neil Heywood.

"The Wang Lijun and Neil Heywood cases and Bo Xilai's serious disciplinary violations have brought great damage to the party and country's image," Zhang Dejiang, Chongqing's new party head, said in comments carried in state media.

The incident had also "seriously impacted" reforms and development in the rapidly growing southwestern city, he said.

"We must draw lessons (from the incident)... and earnestly improve our work," he said, according to China National Radio.

Chinese leaders are keen to draw a line under a case that is still shrouded in mystery and has set online tongues wagging, with rumours regularly emerging that other top politicians associated with Bo are in trouble.

The ruling party believes that maintaining an appearance of unity is crucial to avoid instability in the country, and analysts say the incident has shattered this carefully preserved image ahead of the leadership transition.

"The results attained in Chongqing over five years and people's hard work must be strictly separated from the Wang Lijun and Neil Heywood cases, and Bo Xilai's serious disciplinary violations," Zhang was quoted as saying.

Bo was ousted as Chongqing party head in March and then suspended from the party's powerful 25-member Politburo the following month.