Actress Keisha Castle-Hughes is getting behind a push to change citizenship access for Māori born overseas. 

The Waitangi Tribunal's considering a claim by Australian born John Ruddock, which calls the fact his children can't get citizenship, unconstitutional.

Ruddock, who's descended from a Treaty of Waitangi signatory, has citizenship by descent. 

Castle-Hughes she has given evidence, after she struggled to get citizenship for her own daughter.

"Aotearoa is the only place that she can go to kura kaupapa, that she can go to kohanga reo, that she can participate in life as a tangata whenua in that capacity."

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