The city's former director general is fighting back against allegations of collusion that emerged during testimony at the Charbonneau commission.

Robert Abdallah held a press conference this morning to dispute "point by point" allegations launched by former construction boss Lino Zambito, who finished his explosive testimony before the commission yesterday.

"I defy anyone who can come and prove and say he gave me one penny," he said.

Abdallah called the allegations of pocket lining from bid-rigging "unfounded," and said he wanted to set the record straight and provide proof of his innocence.

He released a large document that included copies of company invoices submitted to the city.

"I'm not saying, 'This is what I heard,'" he said, referencing Zambito's admission that he was not a first-hand witness to many of the details alleged in his testimony.

"This is proof that what he is saying is false," Abdallah said.

Zambito testified that Abdallah instructed him through a middleman to use piping from a particular firm while working on a major sewer contract, even though that material was $300,000 more expensive than an alternative.

Zambito says he was informed that difference would go to Abdallah as part of the deal. None of the allegations has been proven in court.

Reverberations from the testimony were felt as high up as the House of Commons, where the government was put on the defensive for once identifying Abdallah as the preferred candidate to run the Port of Montreal.

He did not end up in that position.

Abdallah defended his career path, saying that he had long left the city when he accepted the job and it had no bearing on his time at City Hall.

"It doesn't mean that I managed a major company that I'm a bad apple," he said. "We did a nice job . . .That's it. I wasn't at the city anymore."

He has since retired.