Acting Chief Minister Andrew Andrew Barr.

Acting Chief Minister Andrew Andrew Barr. Photo: Rohan Thomson

The ACT government will reduce its land release program in the June budget as the territory's rate of population growth slows to about 1.5 per cent a year.

Canberra's population growth is expected to slow during the next five years due to public service job cuts, but to grow strongly in coming decades, according to new government figures.

Canberra's population is expected to reach 400,000 by 2017, 500,000 by 2033 and 600,000 by the middle of the century.

The government's projections are more conservative than figures published by the Australian Bureau of Statistics last month, which suggested the number of people living in the territory could be as high as 904,000 by 2061.

The government is basing its figures on an expected fall in interstate migration during the next four years due to cuts to the Commonwealth public service.

The territory's birth rate and rate of overseas migration are expected to grow, but not enough to maintain the 2 per a year growth seen in the ACT in recent years.

Acting Chief Minister Andrew Barr said the government was preparing to slow its land release and infrastructure programs in the June budget.

Mr Barr blamed the Abbott government for slowing the city's development by taking the axe to Commonwealth departments.

''Given that half of all jobs in the city are coming from the major employer, that decision of theirs has to slow population growth,'' he said.

Mr Barr, also the Treasurer, said public service projections in the May federal budget would heavily influence the extent to which the territory adjusted its programs.

He said a boom between 2008 and 2013 ''both in terms of our economy and our population'' would not be replicated in the next four to five years.

''What we'll be looking at is a reduced land release program - releasing land over a longer period,'' he said.

The move would slow commercial and residential development, Mr Barr said. ''The city is going to grow more slowly.''

''That's the bottom line. That flows through to our budget, our infrastructure decisions, the pace of land release, how much commercial and industrial land the market can absorb [and] what demand there'll be for residential land in various locations.''

The government's population projections show an ageing population, with the percentage of Canberrans aged over 65 set to double from the 2012 level of 11 per cent to 22.5 per cent in 2062.

Canberra's median age is expected to rise from 34 to 41 by 2062 and the proportion of Canberrans of working age to decline.

''The pressures in terms of population growth are going to come from an ageing population,'' Mr Barr said.

''There will be fewer people of working age population supporting more people who are not in the workforce.''