Australia is snubbing upcoming negotiations for a treaty to ban nuclear weapons at the United Nations, with the Department of Foreign Affairs saying it wouldn't be able to negotiate in good faith.
A global summit kicks off in late March and a second round of talks begins in mid-June.
Assistant Secretary Jane Hardy told a Senate estimates hearing on Friday Foreign Minister Julie Bishop made the decision not to participate on the advice of the department and other agencies.
"We believe it would send the wrong signal (if Australia attended)," Ms Hardy said.
She argued a potential treaty was against Australia's national interests and won't actually affect disarmament efforts.
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Australia, the United States, Russia, Israel, France and the UK were among the countries last year who voted against a resolution to hold a conference.
A total of 123 nations voted in favour of the resolution while 38 opposed it and 16 abstained.
The conference aims to negotiate a "legally binding instrument to prohibit nuclear weapons, leading towards their total elimination".
Australia relies on the deterrent protection from the US's nuclear weapons arsenal.
