Wellington, June 12 NZPA - After more than a decade of uncertainty about its future, Wellington Hospital's child cancer unit has now been downgraded until at least the end of next year.

The unit has battled for survival over the years caused by the successive departures of its paediatric oncologists.

The latest resignations, of husband and wife team Christian Kratz and Mwe Mwe Chao after less than a year in the job, has again put the future of the unit in the spotlight.

Many believed it could close after Mr Kratz and Ms Chao leave in August.

However, Capital and Coast District Health Board yesterday announced that the unit would provide only a "high-level secondary service" for at least 18 months.

This means families of complex or new patients from the lower North Island face the additional stress of travelling to Christchurch or Auckland for treatment, the Dominion Post reported.

DHB chief executive Ken Whelan said it was "pretty clear" that the hospital could no longer offer a tertiary service.

"(Downgrading) is our safest and only immediate course of action."

Mr Kratz and Ms Chao last month blamed hospital management's "hampering" attitude and lack of support for their resignations.

A locum doctor from the United States will remain at the unit until October.

Mr Whelan said the board would work with a group of families, clinicians and administrators to determine what changes were needed to build a sustainable unit and make tertiary services viable again for sick Wellington children.

In the meantime, the board would provide extra funding and support to families who had to travel to get treatment.