Prime Minister Jacinda Ardern has accepted Minister Meka Whaitiri's offer to stand aside from her portfolios, while an investigation is carried out into a staffing matter in her office.
Newshub understands the probe follows allegations of a physical incident with another staff member in her office, which involved some shoving.
Ms Whaitiri is the Minister of Customs, and is also an Associate Minister for Agriculture, Forestry, Local Government and Crown/Māori Relations.
Ms Ardern was advised of the staffing matter on Wednesday evening.
"Meka Whaitiri has told me she will be fully cooperating with the investigation, which will be thorough and conducted as quickly as possible," she said in a statement.
The investigation will be led by Ministerial Services.
Minister Kris Faafoi will take over as Acting Minister of Customs during the investigation. Ms Whaitiri's Associate Minister portfolios will be delegated to the lead Ministers.
Ms Whaitiri was first elected to Parliament in 2013, and is the MP for the Ikaroa-Rāwhiti electorate.
The announcement comes just six days after Ms Ardern removed Minister Clare Curran from Cabinet for failing to disclose a meeting she had in relation to the Government's Chief Technology Officer (CTO) role.
Ms Curran offered her resignation as Minister for Open Government and Government Digital Services.
Ms Ardern accepted her resignation and then took the step of removing her from Cabinet.
Ms Curran remains the Minister of Broadcasting, Communications and Digital Media.
She failed to record a meeting she held at her Beehive office one evening in February with Derek Handley to discuss the CTO role. It was the second time she'd come under fire for not disclosing meetings.