Prime Minister John Key says he is not embarrassed that he didn't use te reo in the World Cup opening ceremony, when the International Rugby Board chairman did.



Key has defended not speaking te reo on World Cup opening night, saying the ceremony itself showed off New Zealand's bicultural nature.



But Labour leader Phil Goff says Key missed an opportunity during his opening ceremony speech.



During Friday night's ceremony at Eden Park, Key welcomed visitors to the tournament, proclaiming "go the mighty All Blacks".



Goff said the fact that Key's comments were only in English were highlighted by the welcome by International Rugby Board chairman Bernard Lapasset, who greeted the crowd in several languages, including Te Reo.



"I think it was an oversight. It would have been better if he said 'Kia ora koutou', it would have been a nice touch. It would have reflected the welcome to New Zealand and that our indigenous culture is important."



Key said he had only one-and-a-half minutes to speak.



"I could have of course, and for the most part I generally do, but I decided not to on that occasion."



Key said he was not embarrassed that Lapasset had used Te Reo and he hadn't.



"It wasn't an overly conscious thought. It wasn't a highly scripted speech. I could have said 'Kia ora'. I think most New Zealanders know I can say that.



"At the end of the day I didn't."



Visitors would have seen the bicultural nature of New Zealand during other parts of the opening ceremony, he said.

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