A new bid to shut the Greens out of Parliament will ensure that Australia will not be led by a minority Government in coalition with the minor party if the September 7 election fails to decide a clear victor.
Opposition Leader Tony Abbott, who had previously ruled out any deal with the nation's left-of-centre third party, yesterday announced he would direct preferences to Labor ahead of the Greens, placing them last on how-to-vote cards.
Prime Minister Kevin Rudd has also now rejected any formal alliance with the Greens similar to the deal predecessor Julia Gillard made after the 2010 election - although he has not made any announcements on preferences or ruled out any other arrangements.
Both parties want to govern in their own right to avoid a repeat of Gillard's fraught three years in minority government. The Greens say they are in collusion to turn Parliament into a "two-party closed shop".
At immediate risk is the sole seat the Greens hold in the Lower House, won by MP Adam Bandt at the last election with the help of Liberal preferences. The inner-Melbourne seat, clustered in the suburbs surrounding the city's central business district, could now fall to Labor rival Cath Bowtel, the party's Victorian president.