Mr Foley, 44, was elected unopposed after a caucus meeting on Monday morning.

He faces the formidable task of reasserting his party less than three months out from the state election, and positioning himself as a viable alternative to Premier Mike Baird.

"Leadership changes are always difficult, and this one has been no different - it came as a bit of a surprise to everyone and Luke would say that himself," Mr Park said.

However, he was confident of Mr Foley's ability to run a strong election campaign, as he had "great credentials and an enormous amount of experience", as well as a focus on social values.

"I will be talking with him in the next couple of days about the things I think need to be a priority in this region," Mr Park said.

"This includes broader Illawarra issues like the South Coast rail line, the timetable, what we can do in places like Mount Keira and how we can harness the power and impact the university is having in our region."

The Labor candidate for Kiama, Glenn Kolomeitz said Mr Foley's leadership would be a boon for the South Coast.

"Luke has already proved himself to be a good friend to the Kiama electorate and the entire South Coast area," he said.

"In recent months he and I have been working closely together drafting a number of important environmental policies for the electorate, some of which are likely to apply statewide."

Mr Foley, a married father of three, described himself last week as an "unlikely leader". He is a member of the party's Left faction, but was supported to become leader by NSW Labor general secretary Jamie Clements, who leads the dominant Right faction.

He lives in Concord West and is an upper house MP who must find a seat in the lower house.

He intends to seek preselection for the seat of Auburn and wants to contest a rank-and-file ballot.

There is pressure on the current Auburn candidates, sitting MP Barbara Perry and councillor Hicham Zraika, to withdraw from the preselection race.

Former Labor leader John Robertson resigned last month over revelations that he had signed a letter of request for Lindt Cafe gunman Man Haron Monis in 2011 as his local MP. Mr Foley was widely considered the party's best leadership option.

The Mercury contacted Wollongong MP Noreen Hay and Shellharbour MP Anna Watson for comment.