A prominent Australian businessman has argued Australia must limit its population growth because the environment can't cope. Prime Minister Kevin Rudd says he supports a "big Australia", with forecasts the population will reach 36 million people by 2050.
But businessman Dick Smith says there's not enough food and water to go around.
He says Australia should cut its skilled migration intake and encourage people to have fewer children.
"Our politicians are completely letting the Australian public down."
"Nine out of ten Aussies don't want 40 million people here but there's no discussion, there's no debate," he said.
The population debate: can Australia handle it?
Right now, we are in the middle of the biggest population boom Australia has ever seen.
The numbers are staggering. Australia will house 35 million people by 2050. Our population is racing ahead at a faster rate than the US, Britain, and even many developing countries.
Currently, about 443,000 people are added to our population every year. The figure used to be just 220,000.
Never before in Australia have we added this many people.
Debate on population targets immigrants
Australia should consider whether immigration can continue at existing levels as part of a comprehensive population analysis aimed at determining how many people the country can support, the Federal Opposition says.
Update 11 Feb: Too many people packed into dirty, crowded cities
Population is the elephant in the room that we have ignored for too long. None of the issues we face - climate change, housing, energy, healthcare, our environment - gets easier if population grows out of control. I have never felt more strongly about an issue and I want future generations to enjoy this way of life.