UPDATE 12.04PM: Chief Ombudsman Peter Boshier says it's premature to say he's reached a decision on whether a 33-page coalition document should be released.

In a provisional ruling Mr Boshier said he was satisfied the document, the existence of which was revealed by Deputy Prime Minister Winston Peters, didn't play a role in policy decisions.

That could be taken as an indication he's unlikely to order it be released public, but he says he's still investigating.

An Official Information Act request was by Newsroom for the document which reportedly includes details of "various areas of policy commitment and developments", including directives to ministers.

Mr Peters said in late October, after forming government in a coalition with Labour, that the document would be released.

But Prime Minister Jacinda Ardern said the document was actually just negotiation notes and rejected the OIA application on the basis it was not official information.

As part of an appeal application, Mr Boshier read the document and told Newsroom "it has played no part in policy decisions, and is not available to Ministers as reference material when making official decisions".

He said in a statement on Tuesday he forms a provisional opinion in all cases before requesting further information.

"In this particular case, I received the requesters' comments (Monday) night and I plan to consider their points carefully before I issue a final opinion," he said.

National leader Bill English said a fully transparent government wouldn't hide behind the ombudsman.

"There's strong public interest in it and they've heightened that public interest in it by refusing to release it," he said.

Ms Ardern maintains the agreed policies reached in coalition talks have been made public while only undecided potential policy ideas remain undisclosed.