The UK Government will formally express its regret for nine Māori murdered during the first encounters with Captain Cook's crew.
It coincides with the 250th anniversary of Captain Cook's arrival in New Zealand, but the message from the High Commissioner will fall short of an apology.
Matthew Tukaki from the Māori Council says it's not good enough.
"When it comes to saying a simple word like 'sorry', just say sorry," he told Newshub. "Let's get on with life."
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- Capt Cook statue going from mountain to museum
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Meanwhile the Race Relations Commissioner is accusing the UK Government of strangling Pakeha-Māori relations.
Meng Foon is disappointed an apology couldn't be mustered.
"They've been waiting 250 years for a regretful apology," he said. "The Crown should apologise properly, so both parties can move on and build nationhood together."
He told Newshub it would go a long way to help both parties move forward.
The High Commissioner will not comment on Wednesday's ceremony until it has finished, Radio New Zealand reports.
A powhiri will take place at the Whakato Marae at 3pm.