Malcolm Turnbull has revealed Tony Abbott's office knew about a deal struck last year with a Senate crossbencher over shotgun imports.
The prime minister's comment in parliament on Thursday directly contradicted a claim by his predecessor on the ABC's 7.30 program on Wednesday that there had been: "No deals from me. No deals from my office. No deal."
In 2015, Immigration Minister Peter Dutton and Justice Minister Michael Keenan met with crossbench senators David Leyonhjelm and Bob Day to discuss a piece of national security legislation.
The meeting concluded with an email being sent to Senator Leyonhjelm confirming ministers Dutton and Keenan "have agreed" to the 12 month sunset clause and "in return Senator Leyonhjelm will vote against" the amendments in question.
Senator Leyonhjelm said this week he had been dudded by the government because it extended the sunset clause while state police ministers considered the reclassification of a rapid-fire shotgun, the Adler A-110.
Mr Abbott was adamant there had been no agreement.
But Mr Turnbull told parliament, in answer to a Labor question, he had asked his ministers about the agreement.
"As a result of those inquiries I'm satisfied that the minister for justice acted in the full knowledge of the prime minister's office at that time," Mr Turnbull said.
Labor leader Bill Shorten said a "civil war" was under way within the Liberal party.
"We all heard it - that thudding noise as Malcolm Turnbull threw Tony Abbott under the bus," Mr Shorten said.
Mr Abbott read from what he described as an "advisor's note" dated July 23, 2015, relating to a shipload of Adler shotguns which was due to arrive in Australia a month later.
The shipment sparked government action to place a temporary ban on the importation of the shotguns until the states' classification review was completed.
"How can there have been some kind of a deal or concession or weakening for Senator Leyonhjelm on the 11th or 12th of August if the temporary ban was what the government had always intended, pending a permanent resolution of this by COAG?" Mr Abbott told parliament.
However, AAP checked the government's ComLaw website which showed the original regulation had an October 1, 2025 sunset clause and on September 3 the government changed the sunset clause to August 8, 2016.
The two cabinet ministers also appeared to back Mr Turnbull's claim.
"There's no question that at an advisor's level there would have been discussions around this issue," Mr Dutton told parliament.
Mr Keenan told MPs he had "interacted in the usual way, as we would with the prime minister's office ... keeping them appraised of what was going on".
Labor seized on the difference of views, unsuccessfully moving to censure the prime minister for "15 sitting days of unprecedented chaos from a government in disarray".
The government used its majority numbers to defeat the censure.
Mr Turnbull said the import ban would remain in place until the police ministers, who meet in Melbourne on Friday, came to a consensus on a tighter classification for the shotgun, which is currently in the easiest category A.
"Once that consensus is reached then the ban would be lifted and so the import arrangements would then be consistent with the reclassification," Mr Turnbull said.
Senator Leyonhjelm has yet to decide whether to back the government's fresh attempt to restore the Australian Building and Construction Commission, saying he remains "50-50".
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