The Taxpayers' Union is crying foul on Kainga Ora's plans to hire more staff.

A leaked briefing obtained by Newstalk ZB reveals the housing agency wants to take on nearly 500 more full-time staff, in the coming year.

It's now gone back on that figure, saying the number will be 465, and that almost half are needed to fill existing vacancies.

Taxpayers Union Executive Director Jordan Williams told Kate Hawkesby the payroll has been growing fast.

He says it only had 1200 staff in 2017, but that jumped to 2200 last year, and it is now on track to reach 3000 by next year.

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