A motion moved by Labor and supported by the crossbench claimed the premier failed to declared a conflict of interest when dealing with road upgrades affecting former Wagga Wagga MP Daryl Maguire.

Ms Berejiklian revealed to an Independent Commission Against Corruption hearing in October that she had been in a secret "close personal relationship" with Mr Maguire for five years.

The inquiry was set up to investigate allegations against Mr Maguire, who is accused of abusing his public office while serving as a state MP.

Ms Berejiklian was referred to ICAC over matters relating to Mr Maguire in November, and again on Wednesday referred over information that has come to light since the inquiry.

Ms Berejiklian met with Mr Maguire about an upgrade to a road more than 100km from his electorate, which runs past two investment properties he hoped to use as short-term rental accommodation.

Funding for the highway escalated significantly after Mr Maguire's meeting with the premier, Labor claims.

The premier also failed to disclose a conflict of interest over her involvement in planning the M9 Outer Sydney Orbital, it says, with Mr Maguire advising a business which bought land in the area.

"Mr Maguire stood to profit from both the upgrade of the Cobb Highway and from knowledge of the M9's route. He was the premier's partner at the time," Labor leader in the upper house Adam Searle said

"Why in both instance did the premier fail to declare a conflict of interest? Why did she fail to inform ICAC about either of these matters?"

The ICAC inquiry into Mr Maguire's dealings is yet to hand down its findings.

Australian Associated Press