Mr O'Farrell lied to the commission about a $3000 bottle of wine he received from Australian Water Holdings chief executive Nick Di Girolamo, who told the commission he delivered the wine to Mr O'Farrell's home in 2011.

Mr O'Farrell denied the claims, but a handwritten note in which he thanked Mr Di Girolamo for the gift was produced. He resigned last Wednesday.

Treasurer Mike Baird was elected to the role on Thursday, with Transport Minister Gladys Berejiklian as deputy.