The update was signed off during AUSMIN meetings in the US, the annual talks between Australian and US defence and foreign ministers.

Under the agreement, Australia will be allowed to take in nuclear material for the procurement of nuclear submarines.

The terms of the original deal, inked in March 2023, only allowed for the exchange of information about nuclear propulsion.

The agreement was a “foundational document” for the trilateral security pact, Defence Minister Richard Marles said.

“(It) provides the legal underpinning of what we agreed with the US and UK under the banner of AUKUS,” he told ABC Radio on Friday.

“It also affirms that in walking down this path, we will meet our international obligations in terms of non-proliferation.”

As part of the AUKUS agreement, Australia will acquire three Virginia-class vessels from the US before Australian-built nuclear submarines begin operating.

The $368 billion plan will bring eight nuclear-powered submarines into service by the 2050s.

The technology-sharing will include the nuclear reactors required to operate the submarines, Mr Marles said.

However, he said the agreement signed did not mean other AUKUS partners would be able to use Australia to store its own nuclear waste material.

“There’s no circumstance in which we would be taking waste from any other country,” Mr Marles said.

“We will be responsible for our own nuclear waste, and that will involve the disposal of the spent nuclear reactors, and we’re going through a process in respect of that.”

Australia would not be in a position to dispose of any nuclear material in the country until the 2050s, the defence minister said.

Details of the agreement were laid out in a letter to US Congress by President Joe Biden.