Scottish First Minister Nicola Sturgeon told the country's parliament she plans to hold a new referendum on Scottish independence on October 19, 2023.
Ms Sturgeon said on Tuesday that the question to be asked would be the same as in Scotland's 2014 independence vote: Should Scotland be an independent country? The First Minister said she would be writing to British Prime Minister Boris Johnson for permission to hold the referendum, saying it was vital that the vote was legal.
She said the issue would be referred to the UK Supreme Court.
In 2014, a majority of the voters in Scotland, which has a population of 5.5 million, rejected independence. Scotland's semi-autonomous government says Britain's departure from the EU, which was opposed by a majority of Scots, means that the question must be put to a second vote.
Johnson and his ruling Conservative Party, which is in opposition in Scotland, strongly opposes a referendum, saying the issue was settled in 2014 when Scots voted against independence by 55 per cent to 45 per cent.
He has previously refused to issue a Section 30 order to allow a referendum to take place.
Ms Sturgeon maintains that her party's success in local elections last year gives her a mandate for a new referendum.
The Scottish National Party did not win the majority in the Scottish Parliament, but the election of a record number of Scottish Green politicians means there is a majority for a new independence vote.
Ms Sturgeon said that Westminster rule over Scotland cannot be based on a consented voluntary partnership.
She said it is time to give people the democratic choice they have voted for, and then with independence to build a more prosperous, fairer country in a partnership of equals between Scotland and our friends in the rest of the UK.
Opposition parties have criticised Ms Sturgeon for her obsession with holding a new independence vote and said she should instead focus on more practical matters such as tackling the soaring cost of living.
Like Wales and Northern Ireland, Scotland has its own parliament and devolved government and makes its own policies on public health, education and other matters. The UK-wide government in London controls matters such as defence and fiscal policy.