Christine Milne says Labor has walked away from its agreement to form minority government Greens Leader Senator Christine Milne told the National Press Club in Canberra that Labor had walked away from the spirit of its agreement to form a minority government. GREENS Leader Christine Milne has moved to distance her party from the embattled Gillard government, announcing the end of the minor party's alliance with the Labor Party. But the move - which she said was triggered by Labor's mining tax debacle - is not expected to trigger a snap election as the Greens have pledged to still back the government on confidence and supply. Speaking at the National Press Club in Canberra, Senator Milne cited the mining tax (MMRT) and what she called was the government's breach of its commitment by failing to tax mining giants properly. She said the Labor government chose "the big miners" over honouring its agreement with her party. "Labor by its actions has walked away from its agreement with the Greens and into the arms of the big miners," she said. Let's call a spade a spade - by choosing the big miners the Labor government is no longer honouring our agreement to work together and make transparent government. Well so be it. "How it was able to be developed into the interests of the three biggest mining companies in the world, and what the impact will be of its failings on the budget, if it is not fixed," Senator Milne said. "Without the Greens holding the balance of power in the Senate, Australia risks the repeal of the mining tax - giving up on any chance of the Australian community receiving its fair share of the bounty of our mineral wealth," she said. Mr Abbott has vowed to scrap the mining tax if the coalition wins government. The senator said this would lead to a "harsher" society with a "conservative agenda that is the exact opposite" of what Australia enjoyed today. "The threat of an Abbott-controlled Senate is real," she said, saying the Greens senate team would act as a bulwark against an Abbott government. Senator Milne appealed for support for the party's only lower house MP Adam Bandt. She also said the Labor party would never have introduced the carbon price without the agreement it had with the Greens. But she said the Greens would not cause instability and would still honour its agreement to run full term. Senator Milne said she would not allow Labor's failure to honour the "spirit of the agreement" to advance the interests of Opposition Leader Tony Abbott. Prime Minister Julia Gillard has said she intends to call an election in August as September 14. Senator Milne said she had spoken with the prime minister before her speech to let her know what it contained.