For the first time in decades, the Coalition does not exist in parliament.
Former prime minister John Howard has slammed the Coalition split as a "stupid" move and called for the Liberals and Nationals to put aside policy differences to get back together as soon as possible.
Nationals leader David Littleproud this afternoon announced his party would walk away from the Coalition agreement following negotiation breakdowns on policy positions, including nuclear energy, and party room approaches.
He did, however, commit to trying to renew the agreement before the next election.
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Liberal leader Sussan Ley will use her party room to fill the new shadow ministry but said she hoped to reform the Coalition in the future.
Howard, one of the Liberal Party's most respected figures, said the split was a "stupid move" but he didn't think it would last forever.
"Again and again, we've demonstrated that our glory days are when we work together," he told A Current Affair tonight.
"So I would say to both the parties, remember that, and if you've got policy differences, which inevitably you have, resolve them."
Howard declined to blame one party over the other for the split but did weigh in hard on one of those key policy differences.
"I personally think nuclear power is part of the solution," he told Nine's Ally Langdon.
"I think it would be appalling if the Coalition will walk away from nuclear power.
"There's some debate about net zero. I understand that.
"I'm a bit of a sceptic on that, but I don't have a vote anymore. I'm just a former prime minister."
The Liberals will now solely make up the official opposition in parliament.
Nationals MPs and senators will not receive any shadow cabinet positions despite an offer from Ley.
Ley said both parties were stronger together and she would continue to work closely with the Nationals with the hopes of reforming a Coalition in the future.
"While I have enormous respect for David and his team, it is disappointing that the National Party has decided today to leave the Coalition," she said.
"The Nationals' door remains open, and our door remains open, and we look forward with optimism to rejoining at some point in the future."
The new Liberal leader is charging ahead and will draw up an exclusively Liberal shadow ministry, which will be announced in the coming days.
"While today is a lot about internal processes, we must never forget that we are here for the people who voted for us, and those who did not, to present a very strong, positive alternative agenda that meets them where they are, and to continue to work incredibly hard for the Australian people every day," she said.
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Littleproud announced his decision this afternoon following earlier discussions with Ley at her dying mother's home.
"This morning, after the discussions that both Sussan Ley and I have had over the ensuing period, our party room has got to a position where we will not be re-entering a Coalition agreement with the Liberal Party after this election," he said.
"What we have got to a position is that the National Party will sit alone on a principle basis.
"On the basis of looking forward, not having to look back and to try and actually regain important policy pieces that change the lives of the people we represent."
Littleproud said the Nationals would continue to pursue the party's nuclear energy policy, oppose any live export ban, call for a regional Australia future fund, and the forced supermarket divestiture.
He added that the split would give Ley, who was elected Liberal leader just last Wednesday, and her party time and space to determine its path forward following its landslide election defeat.
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The Liberal Party has faced calls to come back to the "sensible centre" of politics and re-work its policy offerings to give it a path back to victory in inner-city and suburban seats that it was all but wiped out of at the election, particularly in regards to the economy, energy and climate, and women.
Howard said "disunity is death" and differences between the two parties would harden the longer the Coalition was separated.
"See this as a short-term mistake, not as a long-term response," he told A Current Affair.
He said in politics things were never as bad as they seemed or as good as they seemed.
Treasurer Jim Chalmers labelled today's split a "nuclear meltdown".
"It is a seismic event in our political history," he said.
"They are a smoking ruin and I think developments today made that really clear."
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Not the first time the Coalition have broken up
This isn't the first time the Nationals and Liberal Party have failed to renew their Coalition agreement since the latter was founded in 1944.
Following Gough Whitlam's "It's Time" victory in 1972, the parties didn't form a combined opposition.
However, they returned to their usual partnership for the 1974 election, which saw Whitlam win again.
More than 10 years later, the campaign by Queensland Nationals Premier Joh Bjelke-Petersen to become prime minister – effectively usurping the prerogative of leadership from the Liberals – again split the Coalition.
The Liberals and Nationals parted company from April to August 1987, but today's split is the first since they came together in the aftermath of Bob Hawke's shattering Labor victory that year.
Ley, however, touched on the Liberal win in 1996, when the party secured enough seats to govern in its own right but chose to honour its agreement with the Nationals.
"John Howard took a strong and principled approach that the Coalition mattered in the long-term more than one term in government, where the Liberals effectively could have governed without the Nationals," she said.
"That is exactly the approach I will take."
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