Prime minister Malcolm Turnbull has reshuffled his cabinet, appointing social services minister Christian Porter as the new attorney-general to replace George Brandis.
As widely touted in the past year, Brandis will be appointed the high commissioner to the United Kingdom, replacing former Liberal foreign minister Alexander Downer.
In a press conference on Tuesday, Turnbull paid tribute to Brandis's 17-year career.
"Firstly, it was on his watch as attorney, and in no small measure thanks to his eloquent advocacy over many years, that Australia legislated for marriage equality," the PM said.
"Secondly, as the minister responsible for domestic national security legislation since 2013, he's undertaken the most comprehensive reforms of our national security laws to keep Australians safe."
Michaelia Cash's portfolio of employment becomes the ministry of jobs, and she also picks up innovation from senator Arthur Sinodinos, who continues to take time off for treatment for cancer.
After creating the home affairs superagency of Australia's national security, border security, and intelligence agencies earlier this year, Turnbull has appointed Peter Dutton as the home affairs minister.
Deputy prime minister Barnaby Joyce will relinquish his agriculture ministry and pick up infrastructure and transport from fellow Nationals MP Darren Chester, who has been demoted from cabinet.
On why Chester was demoted, Turnbull said that the composition of the ministry had to take into account "matters of geography" and said that it was a question best directed to Barnaby Joyce.
"I regret that this has resulted in him no longer being a member of the ministry," Turnbull said.
Nationals deputy leader Bridget McKenzie will be the minister for sport, rural health, and regional communications, and fellow Nationals MP David Littleproud will take over agriculture and water resources.
Minister for justice Michael Keenan will become the minister for human services and assisting minister on digital transformation. Dan Tehan will shift from veterans' affairs to social services.
Kelly O'Dwyer will be the minister for women, while Craig Laundy will be the minister for small and family business, workplaces, and deregulation.
Zed Seselja will be the assistant minister for science, jobs, and innovation, while Angus Taylor will be the minister for law enforcement and cybersecurity, and Alan Tudge will be the minister for citizenship and multicultural affairs.
Michael McCormack will be the minister for veterans' affairs.
Finance minister Mathias Cormann will also take on the role of special minister of state permanently after filling in for Scott Ryan during the postal survey process and once he became Senate president. Cormann will also take on Brandis's role of government leader in the Senate.
Brandis will become the 14the senator to leave the 45th parliament since the 2016 election. The casual vacancy triggered by his resignation means the Queensland LNP will decide his replacement.