Bo Xilai has dismissed testimony from his wife, Gu Kailai, at his trial, saying she was unstable and had been coerced.
Video footage and written testimony from Gu Kailai, who was convicted last year of the murder of Neil Heywood, was posted on the court’s official microblog.
In it she said she felt Neil Heywood was a threat to her son, Bo Guagua.
Gu Kailai also spoke of receiving gifts from a Dalian entrepreneur, Xu Ming, from whom Bo Xilai is accused of taking bribes.
Bo Xilai, the former Chongqing Communist Party chief, is accused of bribery, corruption and abuse of power.
On Thursday he denied bribery, saying he had been forced into admitting it to prosecutors, and rubbished testimony from witnesses including his wife.
Of Gu Kailai’stestimony on Friday, Bo Xilai reportedly said: “In her unstable mental state, prosecutors put pressure on her so she would turn on me.”
Foreign media are not being allowed into the trial, which is taking place in the city of Jinan in Shandong province.
Analysts say the trial is as much about getting rid of a popular politician as it is about criminal wrongdoing. Bo Xilai is widely expected to be found guilty.
Bo Xilai’s downfall was seen as the biggest political shake-up to hit China’s ruling elite in decades. In February 2012 his police chief, Wang Lijun, fled to the US consulate in Chengdu amid an apparent fall-out with Bo Xilai.
Shortly afterwards, Chinese authorities announced that they were reinvestigating the death of Neil Heywood, who died in a Chongqing hotel in November 2011.
Gu Kailai has since been jailed for the murder of Neil Heywood – a crime she carried out, state media say, because of differences over a business deal.
In written testimony to the court, she said she believed that the personal safety of her son “was under threat”.
“In the second half of 2011 Guagua made a video call to me on his iPad telling me that Neil Heywood threatened him,” she said. Subsequent e-mails between the two scared her, she said.
“After the video call I was very worried which led to the 15 November crime [when Neil Heywood was killed].”
Written testimony from Patrick Devillers, a French architect, meanwhile, pointed to conflict between Gu Kailai and Neil Heywood over a financial deal related to a villa in France that has been a focus of the bribery charges.
It was paid for by Xu Ming, the court heard on Thursday, one of two men from whom Bo Xilai is accused of receiving bribes totalling 21.8 million yuan ($3.56 million).
In her video testimony Gu Kailai said it was true that Xu Ming had bought things for her and her son, Bo Guagua.
“When we need to book a flight, family members know to ask from Xu Ming,” she said.
Bo Xilai, responding to his wife’s testimony, is reported to have said: “How much credibility is there are about Bo Gu Kailai’s testimony, and her written material? Bo Gu Kailai has changed and she became crazy and lies all the time.”
It is not clear how long the trial will last. Bo Xilai is the last major player in connection with the Neil Heywood case to face judicial proceedings.
His son, Bo Guagua, remains in the US, where earlier this week he said any verdict would carry no moral weight if his “well-being has been bartered for my father’s acquiescence or my mother’s further co-operation”.
Bo Guagua also said his mother had been unwell since 2006, following a “sudden collapse of her physical health”.