Britain's highest court on Wednesday rejected a bid by the devolved Scottish government in Edinburgh to hold a new referendum on independence without London's consent.
The unanimous ruling by the Supreme Court torpedoed the Scottish nationalist government's push to hold a second plebiscite next year.
The Scottish National Party (SNP) had said that in that event, it would turn the next general election into a de-facto vote on splitting from the rest of the United Kingdom, threatening constitutional chaos.
First Minister and SNP leader Nicola Sturgeon said she respected the ruling but was "disappointed".
If Scotland cannot "choose our own future without Westminster consent", the idea of the UK as a voluntary partnership was exposed as a "myth", she tweeted.
The Supreme Court's Scottish president, Robert Reed, said the power to call a referendum was "reserved" to the UK parliament under Scotland's devolution settlement.
Therefore "the Scottish parliament does not have the power to legislate for a referendum on Scottish independence", Reed said.
Sturgeon's SNP-led government in Edinburgh wanted to hold a vote in October next year on the question: "Should Scotland be an independent country?"
The UK government, which oversees constitutional affairs for the whole country, has repeatedly refused to give Edinburgh the power to hold a referendum.
It considers that the last one -- in 2014, when 55 percent of Scots rejected independence -- settled the question for a generation.
Most voters in Scotland opposed Brexit.
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