Prime Minister John Key says it is not possible to have a debate on election spending without looking at the issue of state funding for political parties.
The question is raised in a discussion paper which will form the basis of the Government's review of electoral finance rules.
Mr Key has previously said the National Party is totally opposed to further state funding for political parties.
He now says there cannot be a wide-ranging debate without at least putting the issue on the table.
Other questions raised in the discussion document include whether anonymous donations should be allowed, and whether limits should be placed on donations or campaign spending.