The government will not say exactly what it has considered or proposed to Defence, but says it is reviewing the Northern Territory's "suitability and readiness" as plans for the nuclear-powered submarine fleet progress.

Deputy Chief Minister Nicole Manison was asked whether the deployment would put the Northern Territory at greater risk from potential adversaries.

She said the territory had "a very long and proud defence history" and listed the upgrades and new construction of new facilities currently underway in the Top End.

"I think territorians are very comfortable with that, they understand our strategic location and generally are very supportive of that defence investment," she said.

To help maximise defence investment in the Top End, Labor created the Canberra-based position of Defence and National Security Advocate to lobby government and industry on the Northern Territory's behalf.

The current advocate, defence analyst Alan Dupont, has previously argued for a Nothern Territory role in the transition to nuclear boats, which may not be ready before Australia's current conventional fleet needs replacing.

a Defence spokesperson said "the development of maritime services and support in Darwin harbour" was covered in "regular, productive discussions with the Northern Territory government on a range of initiatives".

An 18-month joint study with the US and the UK is due to be completed by early next year, but staffers from a high-powered US Senate committee have been visiting Australia for talks this week.

Newly tabled responses to Senate questions on notice show the nuclear-powered submarine taskforce has an approved budget of $120m for the 2021-22 financial year and $180m for 2022-23.

That would include funding for technical studies and travel. It would also cover contributions to other government entities which are supporting the taskforce, such as the Department of Foreign Affairs and Trade and nuclear agencies Ansto and Arpansa.

costs of actually building the submarines are yet to be allocated in the budget

Minister for Defence Peter Dutton and representatives from the United Kingdom and the United States this morning (22 November) signed a legally-binding treaty to grant Australia access to advanced nuclear technology under the AUKUS agreement.

The treaty establishes a framework for the disclosure and use of information related to naval nuclear propulsion, supporting the local development of at least eight nuclear-powered submarines for the Royal Australian Navy.

The agreement also aims to develop the skills necessary to establish a best practice regulatory and safety regime, ensuring Australia complies with its international obligations under the Treaty on the Non-Proliferation of Nuclear Weapons.

“There are plenty of others who don't want to see this go ahead, I think that tells you why it's so important that we do.”