Prime Minister John Key on Wednesday confirmed he had attended 53 Cabinet Club fund raisers since 2008 in his capacity as National Party leader.
Green Party co-leader Russel Norman has damned National's Cabinet Clubs, where members pay to attend functions with senior ministers, as fundamentally corrosive to democracy.
Government ministers questioned about their involvement have said they turned up and spoke to organised events but were not actively touting for donations.
But Mr Norman said the system gave wealthy people more access to the halls of power.
Mr Key said he had attended 53 such fund raisers, and they were completely within the rules of Cabinet.
"They go in their capacity as an MP, they don't go as a party member, they don't go as a minister. But the Cabinet manual also makes it quite clear they're free to actually talk about any portfolio matters," Mr Key said.
Immigration Minister, Michael Woodhouse, today defended his attendance at a fundraiser for Chinese supporters last year, where he discussed immigration matters.
Mr Woodhouse said he was not sure if the event, late last year, was a fund raiser as he did not organise it.
But he said he did nothing wrong by discussing immigration issues at the meeting.
"What I think is appropriate and important is that members of the New Zealand public have access to ministers over issues that concern them," he said.
National Party president Peter Goodfellow said donations gathered from the events were declared and it was within electoral rules.
"I think you can access a minister at any stage - they attend lots of functions in their own electorates," Mr Goodfellow said.
"This is just simply another part of our fundraising - it may be that almost every electorate holds a breakfast or a lunch, some of the them have these Cabinet Clubs."