In her first national keynote address since taking over the portfolio in June, Senator Bridget McKenzie said she wants to invest more in regional cities.

"I envision a future Australia that has many regional cities with populations well in excess of 300,000," she told the Regions Rising webinar in Wodonga on Friday.

The audience, which included one thousand people watching online from Broken Hill to North West Tasmania, was told that for too long there has been a focus on metropolitan Australia.

"A choice beyond the increasingly unaffordable and congested city limits of Sydney, Melbourne, Perth or Brisbane," Senator McKenzie said.

"In an ideal world, I would like ... 50 per cent of future population growth to occur in the regions," Senator McKenzie said.

The Nationals senator said regional Australia had to leverage off the "organic shift" to the regions due to COVID-19, with a net exodus of more 54,000 people out of the cities since the pandemic began.

"COVID has forced so many of us to rethink," she said.

The audience was told the key drivers pushing people to the regions were jobs, affordability and liveability.

Senator McKenzie has instructed her department to identify how regional cities could be "future cities of rapid growth," and become "significant economic centres".

They include those with populations between 25,000 and 250,000, and are at least 90 minutes from a capital city.

But the senator said it's not just about population, and her department would look across 14 factors to determine which centres are doing well, including those with key infrastructure and good connectivity.

"As a government we want to invest in regional centres that are already well-primed for growth," she said.

"As Australia's population grows over the coming years, and it will, we cannot nor should we continue to concentrate growth on capital cities ... particularly Sydney and Melbourne."

The webinar hosted by the Regional Australia Institute was told that regionalisation will help Australia to reduce its carbon emissions.

"Regionalisation offers an alternative path that can relieve the congestion burden of population growth from our capitals while offering better settlement outcomes for all Australians both in the regions and our cities," Senator McKenzie said.

She used California as a successful example of regionalisation, referring to the relocation of the state capital from San Francisco to Sacramento after an earthquake in 1906.

"After embracing decentralisation, that state alone has 75 cities with populations of more than 100,000 people," she said.

But the senator also recognised "not all regional centres will take up the invitation to grow."

Australian Associated Press