The Australian Greens will seek a six per cent wealth tax on billionaires to fund schools and free dental care if the next election ends in minority government.
With the polls pointing to a tight result at a federal election and Scott Morrison's coalition holding the narrowest of majorities in parliament, the Greens could again find themselves at the negotiating table post-election as they did in 2010.
Greens leader Adam Bandt will use an event in Brisbane on Sunday to launch a suite of policies the minor party will take to the election - expected later this year or in early 2022 - as part of its Fight for the Future.
"The next election will be closer than people think," Mr Bandt says.
"At the last election, Australia was only 828 votes away from a minority parliament.
"At the next election, people can kick the Liberals out and put the Greens in balance of power in both houses of parliament, where we will push the next government to go further and faster on tackling inequality and the climate crisis."
He said the wealthiest Australians and largest corporations should pay a higher slice of tax.
"Billionaires and the big corporations have been buying influence over the Liberal and Labor parties with political donations, which is how they avoid paying tax, keep wages low, send their profits offshore and keep on polluting."
The Parliamentary Budget Office found the billionaire's tax could raise $40 billion over a decade.
As well, the Greens want the dole lifted above the poverty line to $80 a day, with government employment programs properly funded.
Other key policies include a treaty with First Nations people and 700 per cent renewable energy, which would include exports.
The party is seeking to win three extra Senate seats and will target up to nine lower house seats, including the Labor-held seat of Griffith in Brisbane.