The Prime Minister is standing by Nanaia Mahuta over claims about perceived conflicts of interest in contracts involving Mahuta's family.

Last month the Herald revealed the Ministry for the Environment had awarded Mahuta's husband and family members contracts worth about $90,000.

Ka Awatea Services, a consultancy Mahuta's husband William Gannin Ormsby owned, was paid $25,000 for work that started in late October 2020.

At the time, Mahuta was the Associate Minister for Education.

Now it has become apparent Kāinga Ora paid Ormsby's consulting firm $73,000 for arranging hui and workshops.

"We stick closely to the guidance of the Cabinet office, as all Governments are expected to do, and that guidance has been followed," PM Jacinda Ardern said today.

"The Cabinet Office have advised that in each of these cases, they believe proper process has been followed."

Ardern said she'd discussed issues where conflicts or potential conflicts of interest had been openly raised.

"I'm confident the process has been followed," the PM added.

Mahuta has also said all potential conflicts were raised appropriately, and the Cabinet manual had been followed.

National Party MP Simeon Brown said the Government must explain what he called an emerging pattern of perceived conflicts relating to Mahuta.

"She is not the Minister for Housing. And I assume she wasn't part of the decision-making process here," Brown told Newstalk ZB.

"It's not just about actual conflicts of interest that matter in these situations but also that all apparent conflicts of interest should also be avoided."

He added: "We've had other contracts going to her husband's firm."

Mahuta is now the Minister of Foreign Affairs, Minister of Local Government, and Associate Minister for Māori Development.