Limits on population should be dictated by infrastructure such as public transport and housing, the ability of the country to ensure lifestyle into the future and a compassionate outlook on the immigration stream coming to Australia.
"We should use the money from the mining boom to skill and re- skill our workforce rather than having hundreds of thousands of people brought from overseas where they may be needed," Senator Brown said.
Meanwhile, Abbott has moved to neutralize Labor's claims he will reintroduce Work Choices, but has refused to guarantee no worker will be worse off under a coalition government.
The opposition leader has said that if he won office there would be no changes to Labor's industrial relations laws for the first three years of a coalition government.
Prime Minister Julia Gillard has dismissed the pledge, saying Abbott could not be trusted on industrial relations because he had always "thought Work Choices was right".
Abbott said Labor was simply scaremongering on the issue.
A Galaxy opinion poll, published in News Ltd newspapers on Sunday, showed Labor maintaining a two-party preferred lead, 52-48 percent, over the Abbott-led coalition.
