The Law Enforcement and Cyber Security Minister Angus Taylor was the most senior Liberal to back Peter Dutton's leadership bid by quitting the frontbench.
Five Liberal frontbenchers have offered the prime minister their resignations, following Peter Dutton’s failed leadership challenge.
Michael Sukkar was the first, stepping down from his office as the minister assisting the treasurer. That resignation was quickly followed by Senator James McGrath, Concetta Fierravanti-Wells and then up and coming Law Enforcement and Cyber Security Minister Angus Taylor.
ACT Senator Zed Seselja tendered his resignation as Assistant Minister for Science, Jobs and innovation later on Tuesday night.
Mr Sukkar’s office confirmed the resignation to SBS News earlier Tuesday evening, revealing via a statement he had voted for Mr Dutton during the leadership ballot.
“In light of today's leadership ballot in which I voted for Peter Dutton, I have offered my resignation to the Prime Minister,” he said.
"As a matter of integrity I felt compelled to do so."
Less than an hour later, a second assistant minister resigned.
James McGrath’s office confirmed to SBS News the Queensland Liberal senator had followed Mr Dutton’s lead and offered his resignation, giving up his position as assistant minister to the prime minister.
His office confirmed the resignation was a matter of integrity after the senator supported Mr Dutton in the Tuesday morning vote.
"I voted for Peter Dutton for Leader of the Parliamentary Liberal Party. As a matter of integrity, this afternoon I offered my resignation to the Prime Minister," Senator McGrath posted on Facebook on Tuesday afternoon.
Senator McGrath was one of the key backers behind Mr Turnbull's rolling of Tony Abbott in 2015.
Later in the evening, NSW Senator Concetta Fierravanti-Wells also handed in her resignation as Minister for International Development and the Pacific, issuing a statement that attacked Mr Turnbull for abandoning the party's conservative base.
"Our conservative base strongly feel that their voice has been eroded," she wrote to Mr Turnbull.
"They needed some demonstrable indication that there are conservative voices around your cabinet table."
Senator Fierravanti-Wells said she pushed for Mr Dutton to replace Julie Bishop as deputy Liberal leader to improve stability.
The Law Enforcement and Cyber Security Minister Angus Taylor became the most senior Liberal to tender his resignation on Tuesday night.
The up-and-coming conservative MP from Goulburn had been enjoying a steady rise in his political profile.
It's understood Mr Turnbull is yet to accept any of his frontbenchers’ resignation.
If he does, it will necessitate a reshuffle of his ministry, something he wanted to avoid before the next election.
“These are people who, for their own reasons, have decided to offer their resignation. But I know that the Prime Minister is working very hard to heal the divisions and to bring the party together," Foreign Minister and Deputy Liberal Leader Julie Bishop told ABC.
Mr Dutton lost Tuesday's leadership ballot with 35 votes to Prime Minister Malcolm Turnbull’s 48.
The former Home Affairs minister has resigned to sit on the backbench, but has not ruled out another challenge.
Mr Dutton would only need seven Liberals to switch their allegiance to succeed in a second ballot.