Chief Minister Michael Gunner has been hospitalised after what has been described as a "minor heart scare".
He has been in Royal Darwin Hospital since Saturday and his office has now indicated he intends to take some time off work to fully recover.
Treasurer Nicole Manison will act as Chief Minister until doctors give Mr Gunner, aged 44, the all clear.
It comes the day after his political adversary, the NT Opposition leader Gary Higgins, aged 65, said he would be standing down as leader because of unnamed health issues.
Ms Manison has told media Mr Gunner's health condition was "a minor issue" and not related to any underlying health problems.
Ahead of the NT's next election in August, Gary Higgins yesterday said he's been dealing with several health problems and made the decision after discussions with family.
Mr Higgins will continue as the Daly local member until the election with his deputy, Lia Finocchiaro, to take over as Opposition Leader on February 1.
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