Treasurer Josh Frydenberg insists historical rape allegations against Christian Porter are finished after the Attorney-General emphatically denied the claims.

But immense pressure remains on the Morrison government to launch an independent inquiry into the sexual assault accusations against the nation’s top law officer.

Mr Porter is expected to be on leave for about two weeks but refused to quit cabinet after vehemently rejecting the allegations.

NSW Police closed an investigation into the matter because of a lack of admissible evidence.

“The matter is at an end because the police have spoken,” Mr Frydenberg told Sky News on Thursday.

“It’s the police whose judgment and whose decision is the most important here.”

The deputy Liberal leader believes Mr Porter’s critics will never be satisfied as he rejected calls for an investigation to review the historical allegations.

“Christian Porter has emphatically denied the events and he’s entitled to the presumption of innocence,” Mr Frydenberg said.

Tweet from @JoshButler

An emotional Mr Porter on Wednesday identified himself as the cabinet minister accused of an alleged sexual assault of a woman he knew 33 years ago.

“It just didn’t happen,” he said.

“Could I have forgotten or misconstrued the things that I have read, which are said to have occurred? Absolutely not.”

The South Australian woman went to NSW police last year but withdrew her complaint before taking her own life in June.

Nationals MP Barnaby Joyce said the Attorney-General’s denial would not stop the “demeaning” speculation on social media about the issue.

“I believe some form of external inquiry would be a vastly better alternative than what we’re seeing,” he told ABC radio.

SA coroner David Whittle has asked the state’s police to further investigate the death.

Police had provided the coroner with a case file on Monday but Mr Whittle found the investigation to be “incomplete”.

“The investigation is continuing and once that investigation has been completed to my satisfaction I shall determine whether to hold an inquest,” he said in a statement.

The woman’s lawyer Michael Bradley has consistently called for an independent inquiry into the matter.

He said it would allow Mr Porter to formally respond and a determination about the allegations to be reached on the balance of probabilities.

NSW independent federal MP Zali Steggall agreed, saying the Australian public deserved to know what evidence did or did not exist.

“The difficulty is the person involved, the Attorney-General, is a person that holds the highest legal position in the land,” she told the Nine Network on Thursday.

“The Australian public must have confidence that the highest legal officer in the land is a fit and proper person for the role and I do think the prime minister needs to lead on this.”

Western Australia Senator Michaelia Cash will act as federal Attorney-General and Industrial Relations Minister during Mr Porter’s absence.

-AAP

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