The National Party's deputy leader says potentially hundreds of cancer patients have had procedures disrupted by Covid-19, and their lives are at risk.
Dr Shane Reti said the Ministry of Health will not say how many patients have been affected.
He has obtained numbers from four of the 20 district health boards so far, which show 85 cancer patients have had their procedures cancelled or delayed since lockdown began.
He said those people need to be prioritised urgently as the patient back-log is worked through.
"As we look to be catching up on that backlog, the cancer people actually need to be front of that queue.
"So it's really important to know what the numbers are and know which DHBs they're in, but that, Andrew Little thinks, is not in the public interest."
Dr Reti said the government was leaving people with cancer behind.