Milne seeks better economic sell

The Greens under former leader Bob Brown could have done a better job of selling their economic vision for Australia, according to the woman who replaced him in the top job.

Christine Milne took over the party's reins on Friday after Senator Brown's shock announcement that he was planning to quit parliament in June.

"The Greens haven't been, I think, successful enough in selling our economic vision, if you like, for the country," Senator Milne said on Sunday when quizzed about the difference between her approach and that of Senator Brown.

"I'm hoping that perhaps under my leadership we can go out with a stronger articulation of not only our vision for the country but how our economic strategy would support it."

The Tasmanian senator said the Greens looked at economic tools as a way of facilitating outcomes for the community in areas such as education, health and welfare.

"Just focusing on economic growth without considering the broader ramifications to the society is actually not improving our health and wellbeing," she said.

Senator Milne spoke with Prime Minister Julia Gillard on Sunday morning and reassured her the agreement regarding the Greens' support for her minority Labor government "stands as it was signed".

Senator Brown on Sunday said it would be a matter for the Greens team whether they chose to support a Tony Abbott-led government if the coalition won the next election.

"If he's elected as leader and the Greens are in the balance-of-power role there is no-one better in this country fitted out and practised to handle that situation than Christine Milne backed up by (deputy leader) Adam Bandt," he told ABC Radio.

Senator Brown said the Greens effectively held the balance of power under the Liberals in Tasmania and they helped achieve law reform for same-sex couples and deliver an apology to the Stolen Generations.

But Liberal frontbencher Christopher Pyne says the new Greens leader won't be as successful as Senator Brown because she won't work with Mr Abbott.

There was a slight possibility the coalition could win control of the Senate at the next election because it would effectively be a referendum on the carbon tax, which Senator Milne had helped to devise, Mr Pyne said.

He said Senator Brown was an astute politician who had seen the writing on the wall for his party after the Greens failed to pick up seats in the most recent Victorian, NSW and Queensland polls.

"It's a clever move because he won't be blamed for the decline of the Greens - he'll go out as the hero," Mr Pyne told ABC TV.

The Liberal frontbencher said Senator Brown's achievement in leading the Greens to their current position with 10 members in the federal parliament was enormous.