National MP Sam Uffindell has been stood down from the party's caucus, pending an investigation into further "very concerning accusations" about his past behaviour.

Party Leader Christopher Luxon says he's been made aware of new allegations about Uffindell's behaviour toward a female flatmate while Uffindell was at university in 2003.

The woman has told RNZ Uffindell was an aggressive bully who once pounded on her bedroom door, screaming obscenities, until she fled through her window.

Uffindell has denied any accusations he was involved in bullying or intimidatory behaviour while at university.

The new allegations came after revelations the new Tauranga MP was involved in an attack on a younger boy while he was at boarding school.

Political Editor Barry Soper joined Heather du Plessis Allan to discuss Sam Uffindell's investigation and more. 

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