Tessa Jowell's estranged husband said yesterday that he would be prepared to testify in Italy against the former Prime Minister Silvio Berlusconi.
David Mills made his offer at Westminster magistrates' court as he gave evidence via video-link to Mr Berlusconi's corruption trial in Milan.
The billionaire media mogul is involved in four cases. One relates to allegations of corruption involving his former tax lawyer, Mr Mills, who is married to Ms Jowell, the shadow Olympics minister and Labour MP for Dulwich and West Norwood.
There were farcical scenes yesterday as British and Italian lawyers struggled to comprehend proceedings in each other's courts. Mr Berlusconi sat expressionless in Milan as the video-link kept disconnecting, while barristers in London had to listen to angry, live exchanges in Italian with no translation.
Both sides expressed dissatisfaction with the translator in Milan. At one point, District Judge Howard Riddle asked why she had stopped translating, only to be told by the translator: "I was getting a bit excited by the tension."
She then had the ignominious task of translating Judge Riddle's remarks back to the Italian court. He said: "We haven't understood as much as we should have done."
Mr Mills and Ms Jowell separated in 2006 after she admitted not knowing he had paid off part of their mortgage with £350,000 at the centre of a bribery case against Mr Berlusconi. The former premier is alleged to have paid Mr Mills $600,000 to lie under oath in two corruption trials in the 1990s.
Mr Mills was convicted of perjury in 2009 but the verdict was later quashed. He avoided a jail term because the case against him expired under Italy's statute of limitations. Yesterday, he told the court he was willing to go to Milan to give evidence, but only if he knew what was expected of him.
So little progress was made that Mr Mills never got round to answering any questions, and the London hearing was adjourned until 19 December.