Norway's right wing has won parliamentary elections, with Conservative Party leader Erna Solberg set to become the country's next prime minister.
Norway has ended eight years of centre-left rule and set the stage for a new Conservative-led government with the populist anti-immigration Progress Party as junior partner.
Incumbent Prime Minister Jens Stoltenberg of the Labour Party conceded defeat late on Monday, while his challenger, Conservative leader Erna Solberg, hailed "a historic election win".
With three-quarters of the votes counted, a bloc of four centre-right parties had won 96 of 169 seats in parliament. Stoltenberg's three-party coalition controlled 72, with one seat going to an independent environmental party.
"In accordance with Norwegian parliamentary tradition, I will seek the resignation of my government after the presentation of the national budget on October 14, when it's clear that there is a parliamentary basis for a new government," said Stoltenberg.
Just minutes afterwards, the nation's likely next prime minister, 52-year-old Solberg, appeared in a triumphant mood in front of supporters in the Norwegian capital.
"Today the voters have produced a historic election victory for the right-wing parties," she said.
The most often-cited scenario prior to the election has been for a minority government made up of the Conservatives and the Progress Party. As of late Monday, it was unclear if the smaller Christian Democrats and the Liberals would seek to join the government or act as legislative support.
The Progress Party looked set to lose 12 seats in parliament, which would leave it with 29. But it still treated the result as victory, as it now faced the first chance in its 40-year history of being part of a government.
"We are going to negotiate a platform for the government, and we have said throughout the campaign that we wanted to leave a serious footprint on the platform," said Progress Party leader Siv Jensen.
Solberg's victory, one of the largest in her party's history, comes despite the fact that the oil-rich nation has fared exceptionally well under Stoltenberg.
"The country is doing pretty well, but that's because of the oil, not because of the leaders," said a 29-year-old voter earlier on Monday after voting at Oslo's city hall.
Having cast his ballot in favour of the Progress Party, he added: "It's time to get a new government."
Stoltenberg's two consecutive terms mark an unusually long tenure, even in politically stable Norway.
During this period, he has steered the nation through Europe's worst post-war economic crisis, warding off any threat to Norway's very high standard of living.
Significantly, one of the top election issues was the proper use of Norway's oil fund, which at $US750 billion ($A817.13 billion) is the world's largest sovereign wealth fund.
Given the general material wealth, and the lack of any serious discontent in society, the weak showing of 54-year-old Stoltenberg's coalition is mostly put down to power fatigue.
"Norway is one of the richest countries in the world, if not the richest, but the generation who made the nation what it is today is not getting to harvest the fruits," said Oslo retiree Espen Ek, who added he had voted "for change".
Stoltenberg's coalition was also criticised for the authorities' failure to prevent right-wing extremist Anders Behring Breivik's July 22, 2011 attacks, causing the deaths of 77 people.
The Progress Party, which counted Muslim-hating Breivik among its members until 2006, has condemned the attacks and has also toned down its rhetoric on immigrants, of which Norway received 70,000 last year, including 25,000 non-Europeans.
No one in Norway associates the party with the carnage wrought by the right-wing extremist - an issue that has been conspicuous by its absence from the campaign.
Instead, the issues that dominated the run-up to the election were healthcare, education, taxes and what to do with Norway's vast oil wealth.