Prime Minister Bill English's center-right National Party won 46 percent of the vote, according to the electoral commission on Sunday. With 61 seats required to form a government, National won 58 with its political ally ACT taking just one seat.

Speaking to his supporters, English said it was clear neither the National Party nor the Labour Party could govern alone and that he planned to start discussions with the New Zealand First (NZ First) party, but added: "We don't need to rush this process."

Jacinda Ardern's center-left Labour Party won 35.8 percent of the vote to take 45 seats while its political ally the Green Party won 5.8 percent for seven seats. 

The anti-immigrant NZ First was in third place with 7.5 percent of the vote, taking a key nine seats.

NZ First leader Winston Peters gave no indication which of the two blocs his party would support and also said there was no rush. 

"As things stand we do have the balance of political responsibility and we're not going to be hasty with that," Peters told his supporters.

"We'll make a decision in the interests of all New Zealand and New Zealand First, that is the whole country, not ourselves in the party but in the national interest and that will take some time," Peters said. 

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Peters helped install a National-led government in 1996 in return for being made deputy prime minister. In 2005, he joined a Labour coalition after being given the job of foreign minister.

He made it clear he was in no hurry to make his choice of partner for the next government: "The writs aren't in until October 12 and nothing can change until that time. We'll have a decision well before that so we invite you to be patient."

Greens leader James Shaw dismissed a coalition with National saying he was "committed to a change of government."

Nail-biting race

There were 3.2 million New Zealanders registered to vote in the election, with a record 1.2 million of them opting to cast ballots early. 

Labour's Ardern was vying to become New Zealand's youngest leader since 1856. Her policy platform included free tertiary education, cleaning up polluted waterways, and curbing immigration to reduce pressure on housing and infrastructure.

The National Party, which has held government for the past three terms, attacked her financial credibility, arguing that only English had the experience to maintain strong economic growth. The 55-year-old ex-farmer and former finance minister took over as prime minister when John Key stepped down in December.  

While Ardern experienced an early surge in popularity, opinion polls showed a swing back to English in the final days of the campaign.

Ardern: no concession

Ardern said on Sunday she would not concede defeat until "we're sure that a stable government has been formed." 

A coalition of Labour and the Greens would also just have enough seats to govern if they teamed up with NZ First.

"At this point the reality for both major parties is they need the support of minor parties to create a government," Ardern told
reporters in Auckland. 

"That's the only point at which there'll be a concession," she said, adding that the parties needed extra time to consider their positions.

Some 400,000 votes will be released after October 7 and analysts say they are likely to boost the results for left-leaning parties.

jm,jbh/se (AFP, AP)