Labour says a new cocktail party recording of National deputy leader Bill English talking about war, the United States and needing to have someone "willing to pull the trigger" shows up the party as militaristic and "unreconstructed Cold War warriors".
Mr English also criticises United States presidential candidate Barack Obama for "being moralistic" about international relations.
National says it is part of Labour's dirty tricks campaign and that it is desperate.
The tape was given to TV3 to broadcast last night on the eve of the United States election and in the last week of the New Zealand general election campaign.
It is not known what question was asked of Mr English to elicit his response - the third secretly recorded conversation with him from the cocktail party held in Wellington at National's August conference.
But as played last night, it said: "I am a bit worried about this whole Obama and Europe thing just because there is a limited effectiveness in being moralistic about international relations, and Europe has turned out to be particularly ineffective even in its own back yard.
"And the US, you can argue, overdo it - and Bush should have put a different window - a different window dressing - there still needs [to be] someone willing to pull the trigger."
Prime Minister Helen Clark said she did not know who was behind the taping.
"What it tells us is how militaristic the National Party is.
"If there is a war going they want to be part of it."
Defence Minister Phil Goff said that while National's "soft words" on wanting an independent foreign policy were a charade, "The reality is that underneath it all, National leaders are the same unreconstructed Cold War warriors they have always been."
Mr English would not be interviewed last night but issued a statement: "Labour and their mates have completely run out of steam and even their dirty tricks are being recycled.
"The public will see this for what it is, a desperate dirty trick three and a half days out from an election. It does not deserve to be dignified with any further response. National remains focused on what matters to New Zealanders."