An ongoing dispute between Australia's top two legal officers has resulted in Solicitor-General Justin Gleeson SC resigning and claiming the relationship is "irretrievably broken".
Attorney-General George Brandis announced Gleeson's resignation on Monday afternoon, saying it was the "proper course of action".
Gleeson advised Brandis of his resignation in a letter on Monday saying it is in "the best interests of the Commonwealth" as the relationship is "irretrievably broken".
"The Commonwealth can be served only when its first and second Law Officers enjoy each other's complete trust and confidence within a mutually respectful relationship," Gleeson wrote in the letter.
The dispute began in October when Brandis claimed he consulted Gleeson over a decision to block all ministers -- including Prime Minister Malcolm Turnbull -- from seeking Gleeson's legal advice without written approval from Brandis.
Gleeson claimed he was never consulted, and the two top legal officers have continued to go back and forth rejecting each others' claims since the dispute began.
The resignation will take effect on November 7 while a Senate committee is due to decide whether Brandis did mislead parliament by November 8.
In a statement released on Monday afternoon, Brandis said "in the circumstances, Mr Gleeson's resignation is the proper course of action for him to have taken".
On Monday night, Treasurer Scott Morrison defended the Attorney-General and called Gleeson's resignation an "honourable" decision.
"The former Solicitor-General put himself in an untenable position when he engaged with the Opposition during the middle of an election campaign," Morrison told The 7:30 Report.
"The Government has to be able to trust its own lawyer. Sadly, I think the course of events we have seen over the various months has led to the position where the former Solicitor-General has taken what I think was the only course of action."
Sections of the letter from Gleeson to Brandis.
I am writing to give you and the Government notice of my intention to resign as the Solicitor-General of the Commonwealth.
I have come to this conclusion with regret, but the best interests of the Commonwealth can be served only when its first and second Law Officers enjoy each other's complete trust and confidence within a mutually respectful relationship. When such a relationship is irretrievably broken, as is the case here, and each Law Officer holds a term of office established by the Constitution or statute which will not expire in the near future, there must be some resolution to the impasse.
Noting that you hold office through the will of the people and are responsible to Parliament, whereas my commission rests on a decision of the Governor-General on advice under a statute, I have determined that I will take the necessary steps to resolve the impasse. My resignation will enable the Prime Minister the opportunity, through the Federal Executive Council, to recommend to the appointment of the 11th Solicitor-General of the Commonwealth.
In taking this step I make it perfectly plain that my motivation is solely to further the best interests of the Commonwealth by enabling the restoration of a functional working relationship between the first and second Law Officers.
For the avoidance of any doubt, I also make perfectly plain that I reject absolutely each and every attack and insinuation that has been made in recent times upon me personally, or upon my office, by Government members of Parliament, including you, in Senate Committee processes. Equally my decision is unrelated to any finding the Senate Committee may make in favour of or adverse to any person.