Kate Washington will not seek to lead the NSW Labor Party.
The Port Stephens MP had been considering joining the leadership race but has instead endorsed former member for Newcastle Jodi McKay, who is now the member for Strathfield.
"Given Jodi's experience as a former minister, her hard work and dedication as a shadow minister, and her strong connection with regional NSW, I firmly believe she is the right person for the job," Ms Washington said on Thursday.
"Jodi's work ethic and strong moral compass will serve our party, our parliament, and the people of NSW incredibly well. She grew up in Gloucester, represented the Hunter region in state parliament previously, and now represents a diverse community in Sydney's inner-west."
Ms McKay will battle Kogarah MP Chris Minns for the leadership after he launched his bid for the job on Thursday.
After losing the March state election, NSW Labor put the process to replace former leader Michael Daley on hold until after the federal election.