Former Democrats leader Janet Powell is seriously ill with pancreatic cancer.
Ms Powell, 70, was diagnosed with the disease a year ago and underwent surgery and chemotherapy.
She has spent recent days surrounded by family and close friends at Cabrini Palliative Care.
''I've been very fortunate to have led a full life,'' Ms Powell said in a statement issued late on Wednesday.
Ms Powell entered the Senate in 1986, filling the casual vacancy of Democrats founder Don Chipp. She led the party from 1990 to 1991, when she lost the leadership as she was negotiating a controversial possible coalition or merger with the Greens.
She resigned from the party in 1992 and completed her term as an independent Senator. She was defeated at the 1993 election.
In 2004, she joined the Greens.
Last year she was appointed a Member of the Order of Australia in recognition of her service to the Parliament and to the community including through her leadership of YWCA Victoria.
Messages for Ms Powell can be sent to firstname.lastname@example.org.