Grant Robertson says Labour hasn't been trying to shield the Prime Minister from the sexual assault allegations plaguing the party.

Jacinda Ardern has denied knowing the allegations against a senior staffer were sexual in nature until details were published by The Spinoff a couple of weeks ago, despite Newshub reporting them early in August.

National MP Nikki Kaye said on Friday it was "problematic" whether Ardern knew or not.

"I think there is either one of two scenarios," she told The AM Show. "One is she knew and that is really problematic for her and there is a trust issue, or she didn't know - and that makes her pretty weak, because I think everyone else in the building knew."

Robertson told Newshub Nation on Saturday there was no policy of shielding Ardern from risky issues, under questioning from host Simon Shepherd.

"No, there's not. And I think it's really important to remember that this is the Labour Party, it is an organisation quite separate from the Government.

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"The party has its own rules and processes, as the Prime Minister has made clear, that process wasn't good, and we need to improve that. I think it's important that as a party, we do take ownership of that. That's what's happening right now."

It's been claimed Robertson was told of the allegations as long ago as June 30. He's continuing to deny that.

"What I've said very clearly is that the allegations that were published on The Spinoff were the first that I had heard of them. Beyond that, I don't want to go into that, because I don't believe that that's in the interests of the young people involved here.

"I'm very comfortable that at every stage of this process, any information I've had I've dealt with that appropriately, I've followed that up, and I've supported people. That's my focus here, not a political game of who knew what when."

Robertson said Labour will happily publish the findings of an inquiry into its handling of the case, subject to redactions for the complainants' privacy. 

"There are some important lessons for us all to learn about how we handle these sorts of situations, so I look forward to the outcome of the review."