Mr Coe's comments follow news the government's land sales profits rose four-fold in just four years, though Mr Coe did not outline how much land he believes needs to be released, or at what price.

A spokesman for Chief Minister Andrew Barr also rejected the suggestion by former Treasury official Dr Khalid Ahmed that the government may have held back releasing land to increase its dividends in later years.

It comes as the average price of a residential block in Canberra has become the nation's second-highest, rents are the highest in the country and the government has faced criticism over the slow progress on a new affordable housing strategy in Canberra.

While Housing Minister Yvette Berry has said the housing affordability was complex and the government would put forward a number of different ideas in the housing strategy later this year, stakeholders were surprised to find no new significant funding injection to address the issue in the latest budget.

But Mr Coe said he believed the crucial issue was supply of affordable land, and given the government was a virtual monopoly land developer in the ACT, it should be releasing more land.

Experts regularly highlight supply as only one of several other factors affecting housing affordability, including income levels for those on low incomes, federal tax policies and a long-term lack of investment to grow public and community housing.

He also said while existing homeowners wanted to see the price of their property go up, prices were rising on the back of some "dodgy fundamentals" and the Opposition believed the solution was to release more land more cheaply.

Mr Coe said while the industry standard for land developers was a profit margin of about 10 to 15 per cent, the government was gouging Canberrans with a net profit margin on residential blocks well above 50 per cent.

"That's why we're seeing land in Gungahlin now going for $1000 a square metre," he said.

Mr Coe said despite the abolition of the former Land Development Agency, the same policies were still at play on land sales as before, as it was the same ministers and the same government involved.

The government's current indicative land release program sets out the release of about 4000 residential blocks a year across the territory, though it does not specify whether housing would be single residential homes or units and townhouses or higher-density apartments.

"The alternative is to release more land and release more land in a structured way," he said.

Mr Coe would not put a specific number on how many residential blocks he would release a year, if voted into government in 2020, but said the rising price of land in Canberra was a clear indicator that at the moment, demand was outstripping supply.

The Chief Minister's spokesman said the government had released more than 40,000 dwelling sites in the past decade and land releases rose from about 3200 in 2013-14 to more than 4900 in 2016-17, though it was unclear how many of those sites were for freestanding homes.

He also said the suggestion the government deliberately held back sales to maximise profit was ill-informed, and due to the time needed to do civil works, it took one to two years for the revenue from sales to flow to Treasury as a dividend.

He also said the rising dividends the government had received in recent years reflected the cycle of land release, development, settlement of dwelling sites, increased supply, and some asset recycling initiative sites.

But Mr Coe said more people in Canberra wanted to buy a freestanding home with a backyard, and he believed they were leaving the ACT to buy cheaper blocks over the border.

It is unclear exactly how many ACT residents may be leaving Canberra to live in New South Wales and commute to the city, though the territory's seven per cent population growth indicates more people are moving to Canberra than those leaving.