Prime Minister Scott Morrison says he wasn't going to risk the AUKUS agreement by informing Labor about the negotiations too early, after reports a lack of bipartisanship has put the Americans offside.
Top brass in the United States reportedly entrusted the Liberal prime minister to bring the Labor leader into the tent, requiring bipartisan support before proceeding with the decades-long partnership as a key pillar of the agreement, according to Nine newspapers.
Labor was subsequently informed the day before the agreement was made public in mid-September 2021.
Mr Morrison denied the veracity of the report, saying the government "absolutely complied with all of the issues that needed to be addressed in forming that partnership".
"We understood absolutely what the requirements were and we met them 100 per cent," the prime minister told reporters on Monday.
"I find it passing strange that you think we wouldn't have maintained the absolute discretion, as we did with so many of our own cabinet."
Mr Morrison said the security pact between Australia, the US and the United Kingdom did receive bipartisan support and lauded himself for being the prime minister to secure the agreement.
"This was a process that, for 18 months, painstakingly working through incredible detail, incredibly sensitive issues, highly confidential. This wasn't something I was going to be loose with," he said.
"AUKUS is a groundbreaking agreement, the most significant defence security agreement Australia has entered into in over 70 years. And I was not going to risk that on the Labor Party."
The procurement of nuclear-propelled submarines for Australia through AUKUS is the first time the US has agreed to share its nuclear submarine technology since bringing in Britain in 1958.
Mr Morrison said Australians needed to trust the government which had the foresight to put the agreement together in the first place.
"Previous Australian prime ministers and governments have tried and failed. I was not going to fail," he said.