There are fears New Zealanders who moved to Australia before 2001 could miss out on citizenship.

The Australian law which allows Kiwis to apply for citizenship more easily if they arrived in the country on or before February 26, 2001, is set to expire in October.

Morgan Blake is behind the Facebook page 'Protecting Special Category Visa Holders'.

He told Newstalk ZB's Mike Hosking it was possible the law would be replaced with something entirely different.

"The advice that I got with the lawyer I had helping me out is that you never really when it comes immigration, with the climate at the moment," he said.

"It's probable, but it's one of those things where people will have to decide whether it's something take a chance on, or maybe just go for the citizenship and be protected forever, pretty much."

Blake believes ripping protections away without any warning would be underhanded, as they would have been paying taxes in Australia for many years.

LISTEN ABOVE: Morgan Blake speaks to Mike Hosking