Member for Wanguri Nicole Manison says she has made a "difficult decision" and will not run in the August election for the Labor Party.
"I have loved my job ... It has been a huge honour to represent the community I grew up in and I am raising my family in," she said on Facebook on Friday.
"I can't thank my constituents enough for backing me, and backing me very strongly, for three elections."
Ms Manison has represented Wanguri, in Darwin's northern suburbs, since 2013 and served as deputy chief minister from 2016 to December 2023 when she moved to the back bench.
She lost two votes for NT's top job as chief minister since Michael Gunner stepped down in 2022, despite being widely regarded as the best person for the job and the heir apparent.
The first was to Natasha Fyles and most recently in December to the current chief minister, Eva Lawler.
Ms Fyles resigned as the Labor leader after revelations she held undisclosed shares in a remote manganese mine, while also refusing to investigate its potential health impacts.
Ms Manison said she was looking forward to more time with her family once she steps down.
"For now I will be working hard for you out at Hibiscus and be here until the election," she said.Â
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