By Francois Murphy

VIENNA (Reuters) – The head of the United Nations atomic agency has said the AUKUS deal in which Australia will obtain nuclear submarine technology from the United States is a “very tricky” issue in terms of inspections but in can be managed.

Washington, London, and Canberra announced the submarine agreement as part of a trilateral defense deal. France was angered when Australia threatened to cancel an order for French diesel-powered subs.

Apart from five countries that are recognized by the NPT, this would mark the first acquisition of nuclear submarines by a country party to nuclear Non-Proliferation Treaty. India is not a signatory to the NPT but does have nuclear submarines.

In comments on Tuesday, Rafael Grossi from the IAEA, the agency that monitors the NPT’s implementation, said that it is difficult to answer technically.

Grossi said that a NPT signatory could exempt nuclear material from IAEA oversight, also called safeguards. However, the material can be used to fuel a submarine. The IAEA monitors all nuclear materials to prevent them from making atom bombs. This rare exception is rare.

He explained that a country could take material from inspectors and it would be high-enriched, highly-enriched uranium.

This means that Australia and the United States, as well as the United Kingdom, must enter into complex technical negotiations to ensure that the nuclear non-proliferation system is not compromised.

It was unclear how long these negotiations would take.