New Zealand First leader Winston Peters had a new lease of life yesterday after Prime Minister John Key warned that any new government after Saturday's election could be brought down by Mr Peters.
In a speech, Mr Peters reminded supporters that Mr Key had previously said he would not work with New Zealand First.
However, New Zealand First would co-operate with any minority government whether it was National or Labour.
"But do not expect us to fall over and vote for - or abstain from - voting on issues like asset sales and separatism.
"We suggest that for the next few days we finish campaigning on our issues and let the voters make up their minds," he said.
Mr Peters has taken on two previous National Party prime ministers and won. He was sacked by Jim Bolger, who then had to deal with him in the first MMP government.
Jenny Shipley dissolved the coalition with New Zealand First in 1998 but Mr Peters went on to support former Labour prime minister Helen Clark in 2005 and regain a ministerial role.
Mr Key has been avoiding mentioning Mr Peters, but with the polls showing a possible return to Parliament, the Prime Minister has come out saying Mr Peters would provide instability in Parliament.
Mr Peters said that under MMP, no party had been able to govern alone. He extended an invitation to Mr Key to attend a New Zealand First rally in Aotea Sq tomorrow to have an exchange of views.
He even promised to buy the Prime Minister a cup of tea, but it would be in a takeaway cup, in reference to the cup of tea Mr Key had with Act New Zealand Epsom candidate John Banks.
"We find New Zealand First is being targeted this week by the Prime Minister.
"With some very erratic reasoning, he's blaming New Zealand First for bringing down a government that has not even been voted on.
"All we did was explain our position to voters. We will go into Opposition and keep an eye on things."
New Zealand First would support good ideas and vote against "dumb stuff" such as selling assets like power stations. The party would also block the sale of prime farmland to foreign interests.
New Zealand First would not give any political party a blank cheque to carve up New Zealand and sell it to their mates overseas, Mr Peters said.
"National is spreading confusion. That's because National is confused. National does not have some divine right to do what it likes for the next three years.
"The other parties don't have that right either and neither do we."
Labour leader Phil Goff has avoided commenting on whether he could work with Mr Peters in a Labour-led government.
Keep MMP spokesman Lewis Holden said Mr Key had made MMP work, and the public should have "absolute confidence" in his ability to continue doing so after the election if National formed a government.
New Zealand remained a country that elected major parties to lead governments and achieve the bulk of their programmes.
"John Key has proven he can be a very effective Prime Minister under MMP, as have other MMP prime ministers before him."