Prime Minister Helen Clark thinks the Greens will say before the election that Labour would be the party they could work with in a post-election deal.
Miss Clark also said she would like to be able to involve the Greens in a government.
The Greens were devastated to be shut out of government after the last election as Labour made deals with United Future and New Zealand First.
Following the party's election campaign launch yesterday, Green co-leader Jeanette Fitzsimons said the party would repeat what it did in 2005 by telling voters in advance who it would work with.
Later this week the Greens will release a list of policy criteria against which it would compare other parties' policies and programmes.
"I think you have to do what is honest and you have to act with some integrity, and if people take you for granted well, there's nothing really you can do about that," Ms Fitzsimons said.
Miss Clark told Radio Dunedin today that it would be Labour rather than National whose policies best fitted with the Greens.
"There's no question where the Greens' hearts would lead them to and one hopes their heads follow their hearts as they normally would do," she said.
"I am certainly going into the election saying I would like to be able to be able to involve the Greens in a Government."
At the last election Labour campaigned saying they it would be happy to have Greens in Cabinet but the post-election scenario did not work out.
"New Zealand First was a fraction larger than they were and United Future was hanging in there with two seats. When it came to forming the government United Future and New Zealand First both completely vetoed the Green Party having anything to do with government positions in terms of being ministers," Miss Clark said.
"And that was very disappointing for me because we campaigned on the basis that we would certainly welcome the Green Party in."
Miss Clark said if Labour had insisted on Green involvement National would have formed the Government instead.
Green co-leader Russel Norman told NZPA that Labour and Miss Clark taught the Greens important lessons.
"Labour taught us the value of independence and we've learnt our lesson. (Miss Clark) gave us a good lesson in the political views of the major parties and their political approach," he said.
"I think she made her choice, she made her bed with Winston Peters and Peter Dunne and she's now lying in it."
Dr Norman said the party would work through its process to decide which party it could work with.
Mr Dunne said Miss Clark's comments showed she wanted a more left-leaning government.
He said greater Green influence would mean higher tax, higher welfare spending and a very expensive emissions trade scheme.
"The choices facing voters on November 8 are becoming clearer -- we can have either a National or Labour-led Government driven by extremists from the fringes or a Government being guided by sensible, centrist parties like United Future."
Dr Norman said in spite of the posturing by other parties the Greens had made significant policy gains -- such as $1 billion for insulating and heating homes.
"That will actually make a huge difference to Kiwi families."