LONDON — First Minister Nicola Sturgeon promised Saturday to push ahead with another Scotland independence referendum after her party gained a strong showing in Scottish Parliament elections, setting up a potential clash with Prime Minister Boris Johnson.

Sturgeon said that an independence referendum was the "will of the country," with her Scottish National Party and pro-independence allies taking a majority of the 129 seats after all the votes were counted.

That will probably boost calls to redo a 2014 independence referendum — dubbed "indyref2" — which could lead to the crackup of the United Kingdom under the strains of Brexit and its deep divisions.

The final tally showed that Sturgeon's SNP won 64 seats, one seat short of a majority. But she said that, along with the Green Party, there would be overall support in the Parliament to again bring the independence question back to voters.

“The people of Scotland have voted to give pro-independence parties a majority in the Scottish Parliament,” Sturgeon said late Saturday even as votes were being tallied.

“Given that outcome,” she added, “there is simply no democratic justification whatsoever for Boris Johnson or anyone else seeking to block the right of the people of Scotland to choose our future.”

Britons went to the polls Thursday for a number of regional elections, but the counting has been slower in part because of pandemic-related restrictions.

The SNP wants another swipe at an independence plebiscite, which its side lost in 2014 by 45 to 55 percent. But the SNP insists that views have changed since the 2016 referendum to break with the European Union, which 62 percent of Scottish voters opposed.

Many are calling this past week’s elections the most consequential in Scottish Parliament history. The Scotsman newspaper said that turnout looked set to smash that of previous elections.

Johnson made it clear he would reject calls for a second independence vote, telling the Daily Telegraph: “I think a referendum in the current context is irresponsible and reckless.”

Chris Deerin, director of Reform Scotland, an Edinburgh-based think tank, said the pro-independence majority pointed to a clash, with both sides digging in.

“You’ll have Nicola Sturgeon saying, ‘I won the election, I now have a mandate to hold a second referendum’ and Boris Johnson saying, ‘Well, I’m not giving you one, it’s too soon, you didn’t win well enough.’ ”

“And what happens when an unstoppable force meets an unmovable object? That’s when it gets messy,” he said.

Sturgeon has her own mountain to climb.

She has to win public permission, legal permission, and then the referendum itself. While polls late last year showed a sustained lead for independence — peaking at 58 percent — they have fallen back, following a sexual harassment scandal involving Sturgeon's predecessor, Alex Salmond, and the success of the British vaccine rollout. The country is now roughly evenly split on the issue.

Salmond formed a new party, Alba, which didn’t win enough votes to return him to Parliament.

The SNP has said that it wants a referendum by 2023 at the latest, but polls also suggest that most people don’t want a referendum in the next couple of years.

Many Scots tell pollsters they want their regional government to get the economy back on track from the brutal pandemic losses before they begin to wave the blue-and-white flag for independence.

The British government says that legally, Scotland needs permission from the British Parliament to hold a referendum.

But even if the SNP has to rely on support from the Green Party, it would probably have enough votes to push through referendum legislation. Many analysts expect the Scottish government to then take its case to the courts, where it would argue that the power to call a referendum should rest with the Scottish Parliament.

“The Scottish problem is Boris Johnson’s biggest single political headache,” said Jonathan Tonge, a politics professor at the University of Liverpool.

In Thursday’s elections, Johnson’s Conservative Party picked up seats in local elections in England and took a Parliament seat in a stronghold of rival Labour.

But it’s a different story in Scotland, where the SNP continues to dominate.

There are also reasons to think that the Scottish quest for independence won’t simply fade away.

Demographic trends show that young people are overwhelmingly in favor of Scotland breaking free. One recent poll found that 72 percent of voters ages 16-34 would vote in favor of an independent Scotland.

Robyn Graham, a 19-year-old law and politics student at the University of Glasgow, said that young people “have grown up with the Scottish Parliament and SNP government for most of our lives . . . and we’ve seen time and time again that Scotland’s voice doesn’t matter.”

“You can’t ignore the democratic will of Scotland,” she said. “It’s quite clear that independence is what we are voting for as part of this election.”