London Mayor Joe Fontana was in a Milton courthouse Thursday to deal with a lawsuit filed against him by a former friend and business associate.

Tony Bacsa alleges Fontana owes him $100,000 for unpaid work after a failed Romanian garbage to electricity venture.

From mid-2008 to November 2009, Bacsa was a consultant for GPEC Global, a firm led by Fontana, Derk Maat and Derek Maat. He was hired to establish business connections for the company.

But the company apparently began to have money problems in late 2008.

Outside the courthouse Bacsa says of Fontana, “Personally, I will never trust this man again.”

Inside, Bacsa told the court his $8,000 a month invoices went unpaid, but Fontana told him “The funding is assured. No problem.”

The judge had to calm an agitated Bacsa during the cross examination by Fontana’s lawyer on Thursday morning.

The lawyer grilled Bacsa over the timing of several expense claims and invoices.

He also focused on whether it was Fontana or the company that owed Bacsa money, pointing out that the previous invoices had been paid by GPEC Global, not Fontana.

Bacsa’s wife took the stand next, describing a long, close friendship between her husband and Fontana until 2008 when their business relationship soured.

Bacsa’s daughter Gabriella then testified that Fontana would visit the family’s home and say ‘Don’t worry Tony, you will get paid.”

Derek Maat later testified for the defence, describing Fontana’s role at GPEC Global as chairman, but “with no day to day responsibilities.”

Fontana finally took the stand late in the day, describing a long friendship with Bacsa.

But Bacsa says he now regrets that friendship, “The important thing is that Mr. Fontana get the message that nobody is immune here, everybody has to take responsibility for his actions, or what he’s saying.”

Testimony is set to continue on Friday.