Health New Zealand says it's going as fast as it can to combat huge delays in implementing pay rises.

It's been three months since senior doctors and dentists settled pay negotiations, but most still haven't received agreed increases.

The Association of Salaried Medical Specialists says some of its members have been told they won't get the extra money until June.

Health New Zealand Chief People Officer Andrew Slater says their systems are the problem.

"Most of our payroll systems aren't compliant with New Zealand law, they haven't been for over 10 years. Many of our hospitals- we still use paper time sheets."

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