Congestion across Australia's biggest cities is a "spurious argument" for cutting Australia's intake of migrants, according to economists and demographers, including one who argues the country's ideal population should increase to more than double its current size.

The federal government announced in its budget this month it would reduce Australia's permanent migrant intake from 190,000 to 160,000 per annum in an effort to tackle congestion and improve liveability within our largest cities.