Foreign Minister Winston Peters' suggestion that a trade deal could eventually be made with North Korea is "insane", deputy National leader Paula Bennett says.
Bennett was also critical of Peters for still holding on to a potential free trade deal with Russia, saying it would upset the EU and other countries which New Zealand was in negotiations with.
"Here we are making real progress in two areas that will make a fundamental difference to New Zealand, we have a Foreign Affairs Minister who actually has experience in the job – he knows that his words matter," she told Radio New Zealand.
"So why would you even think about upsetting our potential partners in a trade deal that's going to make a huge difference to New Zealand?
"I don't know what the fixation is with Russia.
"Yes, he didn't say we are going there. But why even talk about It when you know it's got the potential to upset some of these guys we are really trying to negotiate with."
Peters, who is in Europe for trade talks, was critical of Russia for its support of Syria but held on to hopes for a free trade agreement in future.
Even a deal with North Korea could happen one day, he said.
"In the end, we have to deal with the whole world and try and bring them 'round.
"At the moment we are talking to North Korea through the back door, through the United States. This is dramatic stuff and we need to do that.
"So [it is] EU first and other countries, but we hope in the long term we've got a free trade deal with North Korea. But not at the moment."
Bennett, the former deputy Prime Minister, said other countries took any talk about Russia seriously.
"A few months ago when [Peters] was talking about Russia, the word back from the EU and from the UK was that they were not happy, that they were in negotiations with us in good faith and they expected us to be doing that as well.
"Even mentioning Russia at the moment does have the potential to set us back."
The EU delegation in NZ said in November that any moves towards thawing relations with Russia would be viewed in a "very negative" light.
Negotiations over a trade deal were suspended in 2014 after Russia's annexation of Crimea, and the Government has said it will not pursue a deal while US and EU sanctions on Russia remain in place.
Prime Minister Jacinda Ardern sought support for a free trade deal with the EU during her time in London, Paris and Berlin last week.
She also called for leaders to consider a CPTPP-style trade deal across the Commonwealth - an idea championed in the past by British Foreign Minister Boris Johnson as part of the Brexit campaign, and by Peters.