A union representing border workers says there needs to be understanding for those who can't get Covid-19 vaccinations.

Unvaccinated frontline workers have until the end of the month to get the jab,  or be redeployed.

Prime Jacinda Ardern says this is the last call, as it's too risky to have unvaccinated people working at the border.

Unite Union national secretary John Crocker told Heather du Plessis-Allan people who can't get the vaccine for medical reasons need support.

He says there are a number of medications you can't get vaccinated on, if you're pregnant or trying to get pregnant.

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