NSW Liberal MP Matthew Mason-Cox has been expelled from the party after successfully nominating himself as upper house president, in defiance of the wishes of Premier Gladys Berejiklian.
Ms Berejiklian on Wednesday said she had asked NSW Liberal Party state director Chris Stone to boot Mr Mason-Cox from the party.
His expulsion was finalised on Wednesday evening and takes effect immediately. There is no route of appeal.
"The NSW Liberal Party has expelled the Honourable Matthew Mason-Cox for breaching the Party rules," a party spokesman said in a statement.
A dispute over the vacant Legislative Council presidency reached a crescendo on Tuesday night when Natasha Maclaren-Jones - Ms Berejiklian's preferred candidate - assumed the chair in the upper house.
Labor and the cross bench have previously argued Ms Maclaren-Jones was not correctly elected as upper house president and proceeded to initiate a vote of no confidence in her position, which was carried.
Mr Mason-Cox then nominated as a presidential candidate and was elected to the role ahead of Ms Maclaren-Jones by 23 votes to 18.
"It has been a tumultuous day," Mr Mason-Cox said on Tuesday night.
"I ask for your goodwill, for your patience and, indeed, for your better judgment ... we now move to working for the people of NSW again."
Ms Berejiklian earlier on Wednesday said Mr Mason-Cox had to go.
She also made clear a woman should have assumed the presidency, but declined to say if Ms Maclaren-Jones would now be offered a frontbench role.
"There is party discipline and party rules people have to follow, he clearly breached those and it's actually the NSW Liberal Party, the organisation, which has taken the action," Ms Berejiklian told reporters.
"I don't think most people in NSW know or care about it, to be honest ... they just want us to get on with the job of governing.
"I'm not happy people play games during what is a very difficult time."
Transport Minister Andrew Constance was more forthright, saying on Wednesday that Mr Mason-Cox was "a selfish bloke" and "inherently lazy".
"I'm no fan of his and I haven't been for a couple of decades now, so I'm internally smiling about it," Mr Constance told reporters.
"(Former premier) Mike Baird dumped this guy in 2014 as fair trading minister for good reason ... he hardly had a glowing ministerial career."
Mr Mason-Cox was one of three Liberal MPs in 2019 to initiate and then withdraw a leadership spill motion against Ms Berejiklian over her handling of an abortion decriminalisation bill.
Australian Associated Press