Zelensky has spoken to many parliaments around the world since the start of the Russian invasion in February, appealing for more help in Ukraine's war against Russia.

He would become just the second head of a foreign government to address New Zealand's Parliament.

The first was Australian Prime Minister Julia Gillard who spoke in the debating chamber about the trans-Tasman relationship in 2011.

A date for Zelensky's address has not yet been set, but it is understood it won't be this week.

It could happen in the next sitting block, before Parliament adjourns for the summer.

The Business Committee, a group of cross party MPs who decide on the business of Parliament, would have to discuss the address before it could happen.

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It's understood its members are yet to be consulted about the speech.

In April, National MP Simon O'Connor lodged a motion calling for Parliament to invite Zelensky to speak to MPs.

Leader of the House Chris Hipkins said at the time Zelensky was a "busy guy" and it would be "undiplomatic" to issue the invitation.

"I think it is somewhat undiplomatic and almost embarrassing for the New Zealand Parliament to move a motion like that without speaking to the Ukrainian President to see whether or not he wants to address the New Zealand Parliament," Hipkins said.

Prime Minister Jacinda Ardern spoke to Zelensky by phone in June. She had been invited to visit Ukraine's capital Kyiv during her trade mission to Europe but couldn't accept because of logistical challenges.

Defence Minister Peeni Henare visited Kyiv last week.