Foreign Minister Murray McCully says New Zealand has worked on shoring up its relations with other European countries which will limit any ramifications for New Zealand if the United Kingdom votes to leave the EU.
The referendum in which UK voters will decide whether to stay with the EU is on June 23 and recent polls have shown an increase in support for the Brexit (the pro-leave British exit) camp as it nears. Polling shows the two camps are still very close.
Prime Minister John Key has said he would prefer it if the UK stayed in the EU.
Mr McCully said the impact of a Brexit result on New Zealand would be "changes in degree only".
"If the UK were to leave the EU, it would mean an increasing reliance by us on other relationships in Europe that we have regarded as increasingly important anyway.
"It obviously is easier if the UK is in, because we've got a large traditional friend that remains a member.
"But we've been working on the assumption for quite some time that we can't be complacent about the European relationship."
Mr McCully left for Europe last night to visit Finland, Latvia and Lithuania to further foster those relations.
New Zealand had also focused on countries such as the Netherlands and countries in the Balkans such as Croatia.
Germany was also a "top priority" because of its influence.
Mr McCully said he did not expect a Brexit result to have much impact on the rights of New Zealanders to move to and live in Britain. Migration from the EU has resulted in much tighter rules on those from Commonwealth countries.
Mr McCully said if the Brexit camp won, it was likely the only gains for Kiwis would be a "a difference in degrees only, and small degrees at that".
"I think there would be an enhanced sensitivity to migration issues generally as part of the change."
It was inevitable New Zealand's free-trade negotiations with the EU would be delayed if Britain did leave.
"I think everything that is on their trade agenda would slip while they were trying to work through the consequences."
However, he did not believe it would be fatal for the trade deal. Trade Minister Todd McClay has just returned from a visit to Europe where he held talks with France, Italy, Greece, Austria and Slovakia and has also held talks with other EU countries.
France is considered to be the toughest nut for New Zealand to crack, especially in agriculture.
Mr McClay said his meeting with France was "very positive" although it was likely there would be sticking points around agriculture and geographical indicators.
"But there is a growing acceptance that the best place to deal with any issues is in negotiations so I'm very pleased with progress."
Labour leader Andrew Little said while it was up to the people of the United Kingdom, his personal view was that it should remain within the EU.
The UK was one of New Zealand's biggest allies in the EU and Mr Little said that would be lost if Brexit won.
"In terms of the ability to influence what happens in the EU, we are at a significant disadvantage."
Britain votes on June 23 whether to stay, or leave, the European Union.
Polls show the decision is tight. An Observer survey yesterday had support for remaining in the EU at 44 per cent with 42 per cent in favour of leaving.