It is "highly unlikely" National will include New Zealand First in its third term of Government, National's campaign director Steven Joyce says.
The leadership team would meet today to discuss who National would work with in Parliament, Mr Joyce told Radio New Zealand, but leader John Key had been "clear last night that we will focus on the three parties that have supported us to date".
"Those are the parties we will turn to for arrangements," he said.
ELECTION INTERACTIVE: Every vote, every seat, every booth
Pushed on what role New Zealand First leader Winston Peters would have, if any, he said: "We will obviously talk with New Zealand First over the course of the coming weeks, but I think in terms of forming a governing arrangement that's highly unlikely to be the path we go down given the way the results turned out."
He believed Mr Peters was "lining himself up for the argument of leading the opposition".
No conversation had taken place about what role Act MP David Seymour would have in Parliament, he said, saying he did not know if he would be made a minister.
"These are the sorts of conversations that will happen over the coming days," he said.
Mr Joyce said National's strong win in the polls was an "endorsement of the direction the party's been going in and the direction the New Zealand economy".
He praised a "very strong turn out", which he believed was driven by the party's core base believing the election campaign scandals would have a detrimental effect on the day.
"There was a sense that they really had to turn out to vote," he said, "and it's what happened and we had a very strong turn out."
Voters were also "determined" that Kim Dotcom "would not have an input into New Zealand politics", he said.