AUTHORITIES in New Zealand have been inundated by Australians checking if they have dual citizenship, on the back of Deputy Prime Minister Barnaby Joyce discovering he’s a Kiwi.

Canberra was rocked yesterday when the Nationals leader revealed he was a dual citizen by descent, with a cloud now hanging over his eligibility to sit in parliament.

He could’ve found out about his problematic status much earlier by answering a few quick questions online.

New Zealand’s Department of Internal Affairs said it has been swamped with queries from Australians checking on their own possible citizenship.

The questionnaire had just 152 page views on Monday August 7 but yesterday saw a massive surge on the back of Mr Joyce’s shock news.

“Yesterday saw this (online citizen tool) page get 17,401 views. This is a 11,348 per cent increase in traffic,” a spokesperson said.

media_camera Barnaby Joyce and PM Malcolm Turnbull during Question Time on Monday. Picture: Kym Smith

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“There has been a large increase in traffic to the online citizen tool in the last few days, with 88% of this traffic originating from Australia.”

A person whose parent held New Zealand citizenship when they were born is automatically considered one too in most cases, the government says.

media_camera Being a New Zealand citizen by descent is automatic in most cases. Picture: AAP

It doesn’t require any paperwork or other processes to formalise the citizenship.

This is the tricky case for Mr Joyce, who now faces the High Court examining whether he can remain a member of parliament.

Wondering if you’re a Kiwi too? You can check here.