Ardern says Parliament, like any other workplace, must be free from bullying and that expectation applies to everyone, including MPs.
"Since the Francis report, we have better processes and procedures in place at Parliament, to identify concerns, intervene early to address them, and to help MPs to be good managers of staff - and that is exactly what has occurred here," she says.
It comes after Labour's Whip's office said it had always acted in good faith with Hamilton West MP Gaurav Sharma, after he made the explosive allegations about bullying.
Ardern says the focus with Gaurav from the start has been on a constructive approach to set him up for the long term as an MP, with coaching, mentoring and other supports.
"Starting out as a new MP can be challenging and one of the toughest parts is navigating the new environment but also the role you must play as an MP managing others."
The Parliamentary Service did put a hiring pause on his office, she says, to "ensure that coaching and mentoring was constructive, and a way to resolve some of the issues in his office that had been raised".
She says she's confident that successive Labour whips and Parliamentary Service have done their jobs appropriately.
"My primary concern at the moment is Gaurav's wellbeing. I've reached out to assure him that we will reach out with the support he feels he needs. Members of our team are in contact with him to make sure that he is okay.
"While we dispute the allegations that he has made, I want to ensure that he knows he is a valued member of our team and I want to ensure he gets the support he needs too."
Ardern says she has never worked with a better group of people, and while no one can claim perfection she's confident Gaurav's concerns do not reflect a wider issue.
She says there are expectations in her team relating to the privacy of others, and clearly there are a number of concerns here at play.
"There are things we need to work through but my primary focus here is on resolving the matter at hand - down the track we can look at the way it has been raised."
She says the focus at this stage has to be on resolving the staffing issues within Sharma's office before the manner in which it has been raised "which because it relates to other staff members does really raise a number of concerns".
Asked if Sharma himself was bullying, Ardern says she will not put a label on it.
She says she was aware at the end of last year there were some concerns and "all parties were working to resolve them" but the next time it was raised with her was "in the media yesterday".
"What we also need to respect here is that there are other individuals involved and they are employment related, so we need to make sure we maintain some confidentiality for those parties too."
"From my perspective is all I've seen is constructive attempts to try and resolve these issues. Even when you engage in what you believe is a constructive way, others may interpret that differently. That is for us to resolve but I believe it can be resolved."
She refuses to speak about the nature of the problems in Sharma's office, citing confidentiality.
"Our MPs employ up to three staff each, often two in their electorate and one in Wellington. That's a number of people that are engaged by our members of Parliament and I have a trusted relationship with the whips and the Parliamentary Services who are all involved in those employment relationships that they have good processes."
In a statement earlier, chief whip Duncan Webb said his office became aware of issues between Dr Sharma and his staff a year ago, and had been trying to work with him to address issues between him and his staff as recently as yesterday.
He said hiring into Sharma's office had been paused to provide "further assistance".
"At all times the Whip's office has acted in good faith and sought to work constructively with Gaurav and the Parliamentary Service to ensure he has good support available to address issues between him and his staff.
"It recently paused hiring with the intention of providing further assistance before more staff were hired into his office. This seemed prudent. The Parliamentary Service and I met with Gaurav in good faith to progress these issues as recently as yesterday, he was fully represented at that meeting.
"We are mindful these are ongoing relationships, so we must respect individual's (sic) privacy."
The Whip said the office would continue to seek a resolution with Dr Sharma in the coming weeks.
column by Labour's MP for Hamilton West Gaurav Sharma, published in the NZ Herald, yesterday laid out a litany of complaints about a culture of bullying he said was supported by those intended to police such problems.
He levelled criticisms against the Prime Minister's Office, Labour's Whip's Office, the Parliamentary Service, and others.
"If any of my more recent colleagues could speak freely, I am sure the list of similar stories with no support for MPs being bullied and no consequences for MPs bullying their colleagues would easily fill a book or two," he wrote.
He said the Parliamentary Service stonewalled and ghosted MPs, and the party whips gaslit and victimised complainants.
The Parliamentary Service yesterday dismissed the allegations, saying it works alongside whips from all parties and had been working over the past year with Labour's Whip's office to address employment matters.
RNZ has contacted Sharma and the prime minister's office for comment. Ardern is expected to speak to media this afternoon.