Labour says the Health Minister owes an apology to thousands of New Zealanders who have found themselves dumped from hospital waiting lists.
There are estimates that as many as 160,000 people have been taken off waiting lists in the past five years.
Jonathan Coleman told TV3's The Nation that the number of people who had been wrongly taken off the waiting lists needed to be clarified.
Labour's associate health spokesperson David Clark said the government had previously denied the existence of hidden waiting lists and must now step up and face the public.
"The government has finally admitted ... that tens of thousands of people are missing out. They've been give the brush off.
"Previously they've denied there are hidden waiting lists. Admitting there's a problem is the first step towards a solution."
New Zealand First health spokesperson Barbara Stewart said the government should look into how people find themselves bumped off hospital waiting lists.
"We get more complaints about people being dropped off the waiting lists than anything else.
"People are out there waiting for operations and the bottom line is that they're not getting them. Its a bit like playing roulette with people's health.
"It seems that the points system has changed and people dont get the required number of points and they're referred back to their GP."
Dr Coleman said it was clear the number of operations being carried out in public hospitals had increased under National.
But Ms Stewart rejected Mr Coleman's statement as anything to do with waiting list numbers.
"The population is increasing. People are needing more health care and more operations and the bottom line is that the facilities aren't there."