A former Labor MP has been accused of lying after he told a corruption inquiry that a billionaire property developer banned from giving political donations volunteered to be a "delivery man" to hand over a bag of other people's cash to the NSW Labor Party's head office after a fundraising dinner.

Ernest Wong told the Independent Commission Against Corruption that the banned political donor, Huang Xiangmo , offered to take the bag at the end of the March 2015 fundraising dinner, which is at the centre of the corruption inquiry.