Greens spokesperson on sustainable cities Senator Scott Ludlam said the National Sustainability Council's report released today "drives home the need for new thinking on urban planning to deal with growing populations, pollution, congestion, and housing affordability".

"Bad urban planning has turned up bad results. People are struggling to find affordable places to live and are spending more time and money getting to and from work. Poor planning costs the economy and the environment.

The State of the Cities Report shows the urgent need for a coordinated approach to transport and housing, Australian Greens sustainable cities spokesperson Senator for Western Australia Scott Ludlam said today.

"The Report vindicates what advocates of sustainable urban planning have been saying for more than a decade," Senator Ludlam said. "On one hand the supply of housing is not meeting demand, on the other hand urban sprawl solves one problem by creating more problems."

Tony Abbott's decision to rule out a conscience vote for Coalition members on marriage equality again demonstrates he's out of touch with what most Australians want, the Australian Greens said today.

"Numerous surveys show Australians want their MPs to have a conscience vote on same-sex marriages," Greens' marriage equality spokesperson, Sen. Sarah Hanson-Young, said today.

"Mr Abbott should stop swimming against the tide of public opinion and let his Coalition MPs have a free vote when the legislation is presented in parliament next year.

Audio from Sarah's door stop in Adelaide on the Liberals and a conscience vote on marriage equality.

The Australian Senate has today agreed, without division, to the Greens’ motion for Australia to take a lead role in devising how we globally accommodate an inevitably greater population within our finite planetary boundaries.

Australian Greens population spokesperson Senator Larissa Waters welcomed the unity of the Senate on her joint motion with Senator Bob Brown on the important issue of sustainable global population.

At this lively IQ2 debate in Sydney, hosted by the St James Ethics Centre, Senator Larissa Waters debated the proposition “If we keep populating we will perish”.

By the end of the night, Senator Waters' team won as the negative team failed to sway the crowd on the night, with the pre-debate undecided mostly joining the 63 percent in favour of the notion.

The speakers were:

The affirmative team
Dick Smith
Professor Steve Keen
Senator Larissa Waters

This month the world is learning about the ongoing famine in the Horn of Africa, where about 12 million people have been hit by the worst drought in almost 60 years. Australia has pledged more than $11 million in aid. It's heart-wrenching to see malnourished children in refugee camps in Kenya with tubes in their noses to feed them because their hungry mothers cannot.

The fact that Australia’s population is now 800,000 above earlier projections is due to big business demanding a huge influx of business and skilled immigrants to match the mining boom in recent years Australian Greens Leader Bob Brown said today.

“We will not get a sustainable population if government bends to big business demands like that,” Senator Brown said.

“We should be skilling our own workers to meet demand.

“Now that Julia Gillard has backed down to mining interests there will be billions less in tax revenues to do that.

The Coalition's Senate vote against an Australian Greens' motion for a national inquiry into population is a somersault on previous statements.

"In March, the Opposition immigration spokesperson Scott Morrison supported the Greens' call for an independent inquiry," said Australian Greens leader Bob Brown.

"Mr Morrison recognised the desire in the Australian community for debate on population.

"Now suddenly the Opposition has back-flipped and voted 'no' to an inquiry."

The Government also opposed the Greens' motion.