Christmas and New Year's leave has been cancelled for military personnel set to cover for striking from non-uniform staff.

The Defence Minister last month invoked the Defence Act, letting uniformed servicemen and woman fill the gaps.

Advocacy group Mission Homefront has written to Judith Collins - saying that's unprecedented and unacceptable.

Co-founder Hayden Ricketts says uniformed staff already give so much.

"You know, those uniformed staff have worked their butts off during the Covid-19 response, they occupied and looked after our country and MIQ and the managed isolation facilities, they've done their best through Cyclone Gabrielle."

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