Tourists are clocking up millions of dollars in unpaid medical bills, and the Green Party is calling for a crackdown.

Figures show between 2013 and October last year, DHBs spent $160 million on patients not eligible for public healthcare.

Green health spokesperson Julie Anne Genter told Mike Hosking DHBs need more help in chasing debt.

"It's a surprising amount of money that would make a difference to our public health system, which is already quite stretched."

Genter said debt recovery should be the responsibility of the Ministry of Health.

"Many visitors to New Zealand won't use the health system, so we have to find a fair way so that those who do are able to get the health care they need while they're here."

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