The Labour Party is defending selling tickets to the business community for $1795 that would grant access to prominent ministers - including Jacinda Ardern.

Invitations to the "Labour Party Business Conference" were recently emailed out by Labour Party president Claire Szabo to businesses.

"We've confirmed attendance from the Labour leader Jacinda Ardern, Labour finance spokesperson Grant Robertson, Labour environment spokesperson David Parker, Labour local government spokesperson Nanaia Mahuta, and Labour transport spokesperson Michael Wood. Each will be running sessions at the conference about Labour's work in their area of expertise," the invitation said.

"The conference includes morning and afternoon tea, lunch and networking drinks at the end of the day."

Labour Party general secretary Rob Salmond said there was nothing in the conference that was against the rules.

"For many years political parties have hosted events which their MPs attend, and sold tickets to those events. There's nothing new in that."

The National Party also drew criticism for its so-called Cabinet Club, where people could pay $1000-plus to chat to senior ministers.

Politicians have long defended the practice, saying it is innocent and necessary in the absence of state funding.

While Labour's conference is within Parliament's and Cabinet's rules, it has drawn the ire of other parties.

"Either the New Zealand business community is queuing up to learn how to run a student union and a fish and chip shop, or it's straight-out graft," Act leader David Seymour said.

Green Party justice spokesperson Golriz Ghahraman said Labour's conference was "problematic" for two reasons.

The first is that the donations to Labour for the conference are about access, which is quite different from someone donating to a party because they believed in the party's policies.

The second is while all parties held fundraisers attended by their MPs, Labour's conference had inequity of access because not everyone would be able to afford it.

"We keep having these things be revealed to the public, and find that the public is shocked and horrified that these things can happen within the rules," Ghahraman told the Herald.

"It's all within the rules, so it's really time to change the rules, even though politicians have a vested interest in the rules remaining."

She has a member's bill in the ballot for a number of changes to electoral laws, including lowering the threshold for anonymous donations to from $1500 to $1000.

Asked whether access to ministers was legit, she said the Electoral Commission should be asked for recommendations.

"Successive governments have buried Electoral Commission reports on how to strengthen democracy. So we need to go back to them and say, 'tell us how to fix this'. And then take the recommendations without party politics coming into it."