National's asking questions about another Cabinet Minister's conflict of interest just two weeks after Michael Wood resigned from Cabinet over un-declared shares.

Simeon Brown claims that it involves Associate Health Minister Peeni Henare and his partner Skye Kimura, the CEO of ad agency Tatou.

He claimed to Heather du Plessis-Allan there have been several contracts between the Ministry of Health and Tatou, but the pair's relationship doesn't seem to have been raised.

He says the Cabinet manual is clear about declaring and managing conflicts of interest.

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