Controversial asset sales legislation has scraped through its latest stage in Parliament amid claims from Opposition parties and protesters that the Government is ignoring public opinion.

The Mixed Ownership Model Bill will enable the Government to sell up to 49 per cent of Genesis, Meridian Energy, Mighty River Power and Solid Energy, and passed its second reading last night by 61 votes to 60.

People Power Ohariu, a group trying to convince their local MP and the United Future leader Peter Dunne to change his crucial support vote, yesterday held a small but rowdy protest at Parliament.

Spokesman John Maynard said stopping asset sales was even more important following reports the Trans Pacific Partnership free trade deal currently being negotiated with nine nations could enable investors in New Zealand companies to sue the Government.

"This is only just coming into public consciousness and it is a vital issue of New Zealand sovereignty."

A coalition of Opposition parties, the Council of Trade Unions, Greenpeace, Grey Power and the Association of Student Unions are currently gathering signatures to force a citizen's initiated referendum on asset sales.

Greens co-leader Russel Norman said the Government should not proceed with the sales until after a referendum is held.

Prime Minister John Key has dismissed the call, saying a referendum was effectively held in last year's general election.

"It was the most critical issue that was debated during the campaign. We had polar opposite positions expressed by Labour and National.

"National won with the biggest result it's ever had in MMP history and Labour had the worst result. So the people of New Zealand have spoken."

However, Norman said National campaigned on a number of policies and many people voted for Key despite opposing asset sales.

"When you look at opinion polls, clearly New Zealanders do not agree with the privatisation programme."

Maynard said the election was not a referendum on asset sales and continuous polling has shown up to 80 per cent of the public were opposed.

"The election was almost a beauty contest for John Key because he wouldn't do serious interviews."

Labour's state-owned enterprises spokesman Clayton Cosgrove told Parliament the Government was capable of listening to the public - evidenced by Education Minister Hekia Parata's backdown over class sizes.

"If the criteria is that the people do not like it and will not wear it, they did it with education, I say colleagues, they should do it with SOEs."

NZ First leader Winston Peters told Parliament National MPs would remember last night's vote because they would be punished by voters on election night 2014.

"I am going to phone all those that lose and say 'remember you were warned'."

State Owned Enterprises Minister Tony Ryall the sales were needed to help the Government get the Crown accounts back into surplus.

"Over the next three to five years the $6 billion in proceeds from these share offers will pay for priority new public assets like modern schools and hospitals through a new Future Investments Fund.

"That is $6 billion we would otherwise have had to borrow from overseas lenders."

The first company to go on the block, Mighty River Power, is expected to go on offer in the third quarter of this calendar year, "markets permitting".

A spokeswoman for Ryall recently clarified that was the third calendar year quarter, so anytime from July.

- © Fairfax NZ News