Green Party leader James Shaw says his goal is to be at the heart of the next government.
Watch James Shaw speaking to Morning Report's Susie Ferguson:
Both National and Labour are looking to strike a deal with New Zealand First leader Winston Peters to form a government.
The Greens won 5.8 percent of the party vote, giving it seven seats, with special votes still to be counted.
Mr Shaw said a majority of New Zealanders voted for the opposition and that showed there was a mood for change.
He said Mr Peters would prefer to negotiated with the largest bloc first, and would be more comfortable talking with the left if they gained more seats once special votes were counted.
Mr Shaw said he would not speculate on the outcome of the talks but his goal was to be at the heart of government.
"I do believe we've learned our lessons over the past 20 years of MMP that for the Greens to advance our policy agenda that we need to be in government and in Cabinet."
Outgoing New Zealand First MP Richard Prosser said his "gut feeling" was that Mr Peters would form a coalition with Labour and the Greens if he could.
"One of the clues, I think, is that through the whole campaign he never actually ruled out the Greens - which is something that he's done in the past," he told Morning Report.
Mr Prosser said under James Shaw's leadership it was possible the parties could come to an accommodation which gave the Greens some influence but kept them away from the "levers of the economy" - the single biggest difference in the parties' policies.
Mr Prosser, who moved down the party's list before the election and will not be returning to Parliament, said National was unlikely to get a fifth term, and the risk for a smaller party allied to a larger one nearing the end of its life was that it tended to get blamed for everything that went wrong.