National says the Government is "ludicrous" not to release its more detailed coalition deal with New Zealand First.
Last month Deputy Prime Minister Winston Peters said there was a 38-page document that Prime Minister Jacinda Ardern would release.
However an advisor to Ms Ardern now says the document won't be released because it's not an "official" document.
National leader Bill English says he can't quite wrap his head around why there is such a squabble about it.
"It is ludicrous and they should release it. I think they're just creating a lot of fuss by not releasing it," he told The AM Show on Tuesday.
"I'm sure if they listen to themselves they'll wonder why they're sitting on it."
Newsroom requested the document under the Official Information Act but was refused. That refusal is now being taken to the Ombudsman. Mr English says the Government needs to release the document before the Ombudsman makes its decision.
"There does seem to be some dispute between the Prime Minister and Deputy Prime Minister over whether it exists, how many pages it is, what it actually says," he says.
"It's all a bit messy, they're much best to not wait for the Ombudsman."
He warns that the Government's lack of secrecy is bad, and fails to show the openness and accountability it promised.
"A coalition Government has been formed in unusual circumstances, the public deserves to know what they've agreed to do," he says. "It's gotta come out."