Current ACT Chief Minister Katy Gallagher is to resign and run for the Senate, following an approach by federal Labor leaders Bill Shorten and Penny Wong.
Ms Gallagher will resign on Wednesday to seek pre-selection for the Senate vacancy created by Kate Lundy's decision to leave the parliament.
Speaking to media on Friday, Ms Gallagher nominated her deputy Andrew Barr for the leadership.
The move comes one year after the ACT legalised same-sex marriage, a bill which was later overturned by the High Court.
Comment has been sought from Mr Barr.
