Prime Minister Jacinda Ardern extended her condolences to Poland over the deadly missile strikes that occurred there overnight, and urged caution over any escalation of the conflict into an even wider war.

Ardern said she was waiting for the outcome of a Nato investigation into what happened before deciding on the next course of action.

“Everyone of course has been cautious around what the impact of escalation would mean, which is why we want to make sure all the facts are established,” Ardern said.

Overnight, a Russian-made missile from the conflict, struck Polish territory, killing two people. Poland is a Nato member, and a deadly incident on Polish soil raises the prospect of the war dramatically escalating.

Ardern extended her condolences to Poland.

“I want to extend the deep condolences of New Zealand for the loss of the loss of those lives,” Ardern said.

“We are utterly consistent in our ongoing condemnation of Russia’s illegal war in Ukraine, we also condemn all targeting of Ukrainian infrastructure,” Ardern said.

Ardern reiterated previous remarks made at the East Asia Summit in the presence of Russian Foreign Minister Sergey Lavrov.

“As I said in the presence of the Russian foreign minister, this war must end,” she said.

Ardern made the remarks in an unscheduled media stand-up in Vietnam, where she is on her diplomatic and trade mission to Asia.

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Overnight, Nato member Poland said a “Russian-made” missile killed two people in the eastern part of its country near the Ukraine border. Nato is currently investigating the incident and determining what took place.

Nato secretary-general Jens Stoltenberg earlier tweeted Nato was “monitoring the situation and Allies are closely consulting”.

 “Important that all facts are established,” he tweeted.

Ardern said she was waiting on the outcome of that review before deciding on next steps.

“You will have seen that Nato is working alongside Nato members to establish all the facts in what has happened in Poland... we await further information about what precisely has happened. In the meantime, our condemnation remains,” Ardern said.

Ardern said that regardless of whether the missile strike was a “miscalculation” the event came “back to the fact that this is an illegal war that must end”.

She said New Zealanders fearing an escalation of the conflict could “take heart from the fact that there is caution being exercised here to establish the facts and what precisely has occurred”.

In New Zealand, Acting Prime Minister Grant Robertson said the news from Poland was “deeply concerning”.

On his way into the House, Robertson said New Zealand continued to condemn the attack.

“This illegal invasion that Russia has undertaken in Ukraine has serious consequences,” Robertson said.

“This is deeply concerning. Obviously, we’ve seen attacks on civilian targets within Ukraine. We don’t know the full circumstances here but we obviously have innocent people in Poland who have now been affected by Russia’s illegal invasion of Ukraine.

“We have to believe in the rule of law and the international rule of law and sovereign countries should not be invaded in the way they have been,” Robertson said.

Foreign Minister Nanaia Mahuta said New Zealand was waiting on the outcome of the Nato investigation before deciding on the next course of action.

“What is important at the moment is we asses the facts of the situation, sadly there has been a loss of life. My understanding is Nato is assessing the facts of the situation, upon receiving a report from that assessment, New Zealand will make a determination,” Mahuta said.

When asked if New Zealand had any defence force personnel in Poland, Mahuta said there were “people in the region”.

New Zealand has an embassy in Warsaw, about 300km from Przewodów, where the missile impact occurred. The Herald has asked the Defence Force for information on personnel in Poland.

When asked if the situation in Poland had changed the Government’s calculus about expelling the Russian ambassador, Mahuta said “actually, it is still an important consideration but it is not the most important act that we can take.

“When we receive the report for consideration of the facts from Nato we will make another set of decisions,” she said.

US President Joe Biden has convened a meeting of the G7 in Indonesia. Indonesia is currently hosting G20 leaders, a group which includes the G7.