Greens leader Christine Milne says Kevin Rudd ''seems to have amnesia'' for saying at the weekend Labor did not have a mandate to introduce a carbon tax.
Calling the Prime Minister a ''flip-flopper'' on environmental matters, Senator Milne said Mr Rudd must have forgotten the mandate Labor got from the public to introduce a price on carbon.
Opposition Leader Tony Abbott will not have a mandate to repeal the emissions trading scheme (ETS) if he is elected, she said.
''We are living in a climate emergency,'' Senator Milne said in an Election Hangout Q&A session on Fairfax websites.
She is confident that if the Greens hold the balance of power in the Senate after the election, it could ''shame Labor, in opposition, into holding the line'' against the Coalition's attempts to repeal the ETS.
Monday's Newspoll survey shows the Greens' primary vote is 9 per cent, down by almost 3 percentage points since the 2010 election.
Despite these disappointing polling numbers, Senator Milne insisted her party would not only hold all its seats in the election, but would pick up a Senate seat in Victoria with Janet Rice.
Senator Milne said she had been out meeting the public and she sensed ''real excitement'' about her party's policies, particularly in Melbourne, where she had spent time with a group of artists.