The New Zealand First Foundation helped fund a New Zealand First MP's trip over to the UK to observe the EU elections.
The entity is currently under investigation by the Serious Fraud Office, following a complaint to the Electoral Commission about its handling of donations.
Money from the foundation went towards Tauranga-based MP Clayton Mitchell's travel costs to the United Kingdom.
The contribution was declared on the annual Register of Pecuniary Interests.
It doesn't specify how much was contributed, but only amounts likely to be over $500 are declared.
The register also shows that the Brexit Party contributed to Mr Mitchell's accommodation during the trip.