A Morrison government cabinet minister accused of a historical rape will reportedly come forward after coming under increasing pressure to publicly identify himself.
Former prime minister Malcolm Turnbull has lead calls for the man to identify himself after Scott Morrison said his cabinet colleague vigorously denied the allegation.
"He should out himself and he should provide a comprehensive statement about what he knows about the allegations," Mr Turnbull told ABC radio on Tuesday.
"If he's vigorously denied the accusations to the prime minister, he should vigorously deny them to the public."
Media are reporting the man will go public on Wednesday after NSW police announced it had closed its investigation into the allegations.
A letter detailing the complaint was sent to Mr Morrison, senior Labor frontbencher Penny Wong and Greens senator Sarah Hanson-Young last week.
The incident is alleged to have occurred in Sydney in 1988 when the woman was 16.
The woman went to NSW Police last year but the investigation was suspended when she took her own life in June 2020 after telling authorities she didn't want to proceed.
The strike force established to investigate the claims confirmed on Tuesday the matter was now closed after reviewing a document thought to be the woman's diary.
"NSW Police have since sought legal advice in relation to these matters," police said in a statement.
"Based on information provided to NSW Police, there is insufficient admissible evidence to proceed."
Mr Morrison and senior coalition ministers have repeatedly insisted the allegation is a matter for police.
Mr Turnbull said the cabinet minister needed to present a comprehensive explanation of his innocence before resuming his duties.
"It's impossible for him to function in that cabinet," he said.
"Are we seriously going to have a Question Time where the opposition asks every single minister whether they are the person named in the complaint?"
Mr Turnbull, who exchanged correspondence with the woman in 2019 about her allegations, is calling for a coronial inquest into her death.
He had a "question mark" over her death because it coincided with the release of explosive sexual harassment allegations against former High Court judge Dyson Heydon.
"It's said that she suicided, did she?" Mr Turnbull said.
"Why did she suicide? Why did she pursue this complaint for so long and then, just at a moment when you think she'd be encouraged, take her own life?"
The South Australian coroner has confirmed the woman's death is under investigation but that doesn't guarantee an inquest.
Labor leader Anthony Albanese said it was untenable for Mr Morrison to allow the issue to drift without further intervention.
"There is a dark cloud now over the government," he told reporters.
The Greens want the minister to stand aside pending an independent investigation by a former judge.
Sexual assault allegations have rocked federal politics for more than two weeks after former Liberal staffer Brittany Higgins said she was raped by a colleague in Parliament House.
Two-thirds of people agree the government has been more interested in protecting itself than the interests of the women who have made sexual assault allegations.
A new Essential poll of 1074 people also found just 34 per cent of people trusted political offices to be safe work environments.
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Australian Associated Press