The government will set up a Grocery Commissioner as a watchdog for the supermarket industry, and is releasing a draft mandatory code of conduct.

Commerce and Consumer Affairs Minister David Clark announced the move during an update on progress made in the supermarket sector, after a major clampdown was announced in May.

Clark said the new Grocery Commissioner role would be part of the Commerce Commission, providing annual reviews of sector competition to hold it to account.

"The Grocery Commissioner will be a referee of the sector, keeping the supermarket duopoly honest and blowing the whistle where it suspects there is a problem," he said.

He said legislation establishing the position would be introduced to Parliament this year.

Commerce and Consumer Affairs Minister David Clark in May signalled a watchdog entity would be part of the government's efforts to rein in the supermarket duopoly, after the Commission released the findings of its market study of the sector in March.

Clark said 12 of the commission's recommendations were now under way, or complete.

"Global factors continue to drive up the cost of living around the world and high grocery prices are making it hard for New Zealanders right now which is why the government has taken a range of steps to take the pressure off immediately while also tackling the underlying problem... lack of competition."

He said he would also be today releasing a draft of the mandatory Grocery Code of Conduct, which supermarket operators would need to abide by.

The code, which had been developed with input from an advisory group, would be particularly important for ensuring small and artisan brands and emerging startups wanting to get their products on supermarket shelves, Clark said.

"Historically, there has been an imbalance in the bargaining power major grocery retailers have over their suppliers. The Grocery Code of Conduct will address this by preventing the major retailers from using their power to push costs and risks onto those suppliers."

Consultation on the code had been set to begin last month. It will now be open for five weeks.

The government last week passed its legislation banning supermarket land covenants, which had allowed existing companies to block competitors' access to sites where they could set up a store.

Other recommendations include implementing a voluntary wholesale grocery access regime - with an option for a mandatory approach if it fails - greater transparency over loyalty schemes and data collection; enabling collective bargaining for grocery suppliers; and a consistent prices display scheme.