Turnbull 'No Grudge' Toward Dutton After Leadership Challenge

Bishop calls 48-35 win an "overwhelming" result for the PM.

Malcolm Turnbull said he bears "no grudge" after seeing off a leadership challenge from Peter Dutton, but the PM is damaged after losing more than one-third of the partyroom support.

Turnbull, after days of mounting pressure, declared the leadership positions of the party open on Tuesday morning, throwing down the gauntlet to a potential challenge. The PM won the vote 48-35, a narrow result. Julie Bishop was re-elected unopposed as deputy leader.

Dutton has now resigned from the ministry and we could see more of his backers step down from the frontbench after their attempted coup. Treasurer Scott Morrison will act in Dutton's powerful home affairs role.

At a 1.15pm press conference, Dutton outlined why he challenged Turnbull.

"I made a decision [to challenge] not because I had any animosity towards Malcolm Turnbull, I made a decision to contest this ballot because I want to make sure we can keep Bill Shorten from ever being Prime Minister," he said.

"I believe I had the best prospect of leading the Liberal Party to success at the next election. That was not to be today".

In what could be viewed as a pitch for support ahead of a second challenge, Dutton outlined what he said would be an election-winning strategy of lower power prices, infrastructure boosts and changes to the migration program. He also reminded people of his long parliamentary CV, running through the various ministry positions he has held.

Dutton did not rule out a second leadership challenge.

At a 12.30pm press conference, Turnbull called for unity. His deputy, Julie Bishop, called the tight result an "overwhelming" endorsement of the PM.

"I don't bear any grudge against Peter Dutton," Turnbull claimed, adding he had asked Dutton to remain as home affairs minister. The Dickson MP decided to resign from cabinet, however, with treasurer and former immigration minister Scott Morrison to act in the home affairs portfolio.

The vote came just a day after Turnbull said Dutton had pledged his support to the PM, and days after Dutton tweeted that the PM "has my support and I support the policies of the Government."

Turnbull had attempted to see off a challenge by retreating on energy policy that was contentious among the conservative wing of his party, but his backdown was not enough. He called a surprise snap leadership vote on Tuesday, before a spill could be called on him by a challenger.

Bishop and Turnbull front media after the vote (AAP Image/Mick Tsikas)

The vote comes a day after Ten News revealed a possible section 44 constitutional cloud over Dutton's business interests which could make him ineligible to sit in parliament.

Losing Tuesday's ballot doesn't mean Dutton's leadership ambitions are totally thwarted. In several previous leadership spills, it has taken two attempts for the challenger to prevail.

Such a situation occurred when Turnbull took the leadership from Abbott, with an 'empty chair' challenge in February 2015 returning Abbott but a September 2015 challenge seeing Turnbull take the top job.

It took two unsuccessful challenges for Kevin Rudd to re-take the prime ministership from Julia Gillard in February 2012 and March 2013, before Rudd finally won in June 2013.

Dutton arrives at the partyroom meeting (AAP Image/Mick Tsikas)

Coincidentally, Turnbull as opposition leader in November 2009 faced a spill motion. He won that vote, as he did on Tuesday, 48-35. The very next day, Abbott publicly challenged Turnbull, and won.

More to come.