Underworld killer Carl Williams warned Tony Mokbel not to trust his barrister-turned-informant Nicola Gobbo.
Mokbel, 58, said he had the conversation with Williams at Barwon Prison after he was extradited to Australia from Greece.
"He just said to me, don't trust her," Mokbel said in his evidence to the Victorian Supreme Court on Wednesday.
"He said other things but I'll leave that aside."
Mokbel is attempting to appeal drug trafficking and incitement to import convictions he was sentenced for in 2012.
In his evidence to the court, Mokbel said he only learnt Williams and Ms Gobbo "hated each other" after she refused to speak to Williams in jail for him.
Mokbel had wanted a statement from Williams that he was not involved in the 2003 murder of Michael Marshall and the 2004 killing of Lewis Moran.
"She said me and him don't get along ... she didn't elaborate much more than that," Mokbel said.
Ms Gobbo was registered as a Victoria Police informer between 1995 and 2010, providing information to detectives about her high-profile clients including Mokbel and Williams.
Mokbel told the court he trusted his lawyer "a million per cent" and he had rejected rumours that she was sleeping with police officers and doing drugs.
"I had no issue with Ms Gobbo," he said.
Mokbel on Tuesday claimed Ms Gobbo was the one who told him to "seriously think" about absconding while he was awaiting trial in 2006 for separate cocaine importation charges.
He doubled down on that claim on Wednesday, saying Ms Gobbo spoke to him on a daily basis about leaving the country otherwise he would be facing multiple murder charges.
"She said 'I've been told if you beat a murder (charge) they will continue to charge you with another one until they find you guilty and they'll give you life'," he said.
Mokbel told the court he did what "everyone with a brain would have done" and fled the country.
The 58-year-old admitted he went into hiding in regional Victoria in March 2006 on the eve of his trial for the cocaine offences.
He was then smuggled across the border to Western Australia, where he hopped on a yacht and sailed to Greece.
Mokbel admitted he had no intention of returning to Australia.
"One hundred per cent, no way, knowing that Victoria Police had it against me," he said.
Mokbel was eventually arrested at an Athens coffee shop in June 2007 but it took 11 months to extradite him to Australia.
He was sentenced to 30 years in prison in 2012 for the drug trafficking charges, as a result of police operations dubbed Quills, Orbital and Magnum.
The sentence was ultimately cut down to 26 years with a non-parole period of 20 years following a Court of Appeal decision in 2023.
Mokbel is now challenging the convictions but before a substantive appeal hearing can start, Justice Elizabeth Fullerton needs to rule on several legal questions.
The justice has been brought from NSW to oversee the determination hearings, which are expected to run for 12 weeks.
Mokbel's evidence will continue on Thursday.
