First minister plays down chances of a referendum this year as she laments Brexit

Nicola Sturgeon has urged supporters of Scottish independence to stay “focused and united”, while ruling out – for now – holding a consultative referendum that would inevitably be challenged in the courts.

Two weeks after the prime minister formally rejected Sturgeon’s request for the legal powers to hold a second referendum, and as a poll put support for independence in the lead – by 51-49 – for the first time since 2015, Sturgeon told an audience of Scottish National party politicians and activists in Edinburgh that she would not “pretend that there are shortcuts or clever wheezes that can magically overcome the obstacles we face”.

Describing Brexit day as “one of real and profound sadness … tinged with anger”, Scotland’s first minister said: “What we in the independence movement must not do is allow a sense of frustration – understandable though it is – to take us down dead ends or weaken our sense of purpose.

“We must not let the Tories turn a positive, persuasive and invigorating discussion about the best future for our country into an arid and bitter argument about process and procedure.”

Pre-empting criticism from pro-independence hardliners, she added: “This isn’t caution talking. It’s realism.”

Sturgeon was addressing activists hours before the UK was due to leave the European Union, despite Scottish voters backing remain by 62% to 38% in 2016. Scotland’s newspapers reflected this fact, with the Daily Record carrying a mocked up image of the Brexit 50 pence coin with the words “Isolated, worse off, weaker and divided”, while the pro-independence National pictured a single candle alight with the plea “Leave a light on for Scotland”.

Facebook Twitter Pinterest Nicola Sturgeon outlines the SNP’s next steps in the campaign for Scotland to become an independent country. Photograph: Murdo MacLeod/The Guardian

At lunchtime on Friday in Glasgow, the president of the European parliament’s Greens, Ska Keller, addressed a rally of Scottish Greens, with anti-Brexit protests also planned in Aberdeen. SNP MPs and prominent independence campaigners will join a candlelight vigil outside the Scottish parliament on Friday evening, while a pro-Brexit celebration was planned for George Square in Glasgow at 11.30pm.

While the SNP leader insisted when questioned by journalists that a referendum was “still practical” this year, her speech suggested her thinking was more pragmatic: “To achieve independence, a referendum, whenever it happens – whether it is this year as I want, or after the next Scottish election – must be legal and legitimate”.

Asked about the likely reactions of disappointment and frustration from the tens of thousands of yes supporters who have taken part in marches across Scotland over the past year, Sturgeon said she had “a duty to be frank”.

Timeline From Brefusal to Brexit: a history of Britain in the EU Show Hide After 47 years and 30 days it was all over. As the clock struck 11pm on 31 January 2020, the UK was officially divorced from the EU and began trying to carve out a new global role as a sovereign nation. It was a union that got off to a tricky start and continued to be marked by the UK’s sometimes conflicted relationship with its neighbours. Brefusal The French president, Charles de Gaulle, vetoes Britain’s entry to EEC, accusing the UK of a “deep-seated hostility” towards the European project. Brentry With Sir Edward Heath having signed the accession treaty the previous year, the UK enters the EEC in an official ceremony complete with a torch-lit rally, dickie-bowed officials and a procession of political leaders, including former prime ministers Harold Macmillan and Alec Douglas-Home.

Referendum The UK decides to stay in the common market after 67% voted "yes". Margaret Thatcher, later to be leader of the Conservative party, campaigned to remain. 'Give us our money back' Margaret Thatcher negotiated what became known as the UK rebate with other EU members after the "iron lady" marched into the former French royal palace at Fontainebleau to demand “our own money back” claiming for every £2 contributed we get only £1 back” despite being one of the “three poorer” members of the community. It was a move that sowed the seeds of Tory Euroscepticism that was to later cause the Brexit schism in the party. The Bruges speech Thatcher served notice on the EU community in a defining moment in EU politics in which she questioned the expansionist plans of Jacques Delors, who had remarked that 80% of all decisions on economic and social policy would be made by the European Community within 10 years with a European government in “embryo”. That was a bridge too far for Thatcher. The cold war ends Collapse of Berlin wall and fall of communism in eastern Europe, which would later lead to expansion of EU. 'No, no, no' Divisions between the UK and the EU deepened with Thatcher telling the Commons in an infamous speech it was ‘no, no, no’ to what she saw as Delors’ continued power grab. Rupert Murdoch’s Sun newspaper ratchets up its opposition to Europe with a two-fingered “Up yours Delors” front page. Black Wednesday A collapse in the pound forced prime minister John Major and the then chancellor Norman Lamont to pull the UK out of the Exchange Rate Mechanism. The single market On 1 January, customs checks and duties were removed across the bloc. Thatcher hailed the vision of “a single market without barriers – visible or invisible – giving you direct and unhindered access to the purchasing power of over 300 million of the world’s wealthiest and most prosperous people". Maastricht treaty Tory rebels vote against the treaty that paved the way for the creation of the European Union. John Major won the vote the following day in a pyrrhic victory. Repairing the relationship Tony Blair patches up the relationship. Signs up to social charter and workers' rights. Ukip Nigel Farage elected an MEP and immediately goes on the offensive in Brussels. “Our interests are best served by not being a member of this club,” he said in his maiden speech. “The level playing field is about as level as the decks of the Titanic after it hit an iceberg.” The euro Chancellor Gordon Brown decides the UK will not join the euro. EU enlarges to to include eight countries of the former eastern bloc including Poland, Hungary and the Czech Republic. EU expands again, allowing Romania and Bulgaria into the club. Migrant crisis Anti-immigration hysteria seems to take hold with references to “cockroches” by Katie Hopkins in the Sun and tabloid headlines such as “How many more can we take?” and “Calais crisis: send in the dogs”. David Cameron returns from Brussels with an EU reform package - but it isn't enough to appease the Eurosceptic wing of his own party Brexit referendum The UK votes to leave the European Union, triggering David Cameron's resignation and paving the way for Theresa May to become prime minister Britain leaves the EU After years of parliamentary impasse during Theresa May's attempt to get a deal agreed, the UK leaves the EU.

“Leadership is not about giving people the easy answers that are deceptively simple but turn out not to be the best way forward. We need to have a process that is legal and legitimate. If I thought a legal challenge would guarantee that process that would be one thing, but it might actually set us back.”

Instead, she told supporters to redirect their energies on “building and winning the political case for independence”.

Sturgeon said she would be doubling SNP campaign spending to focus on undecided voters. In the coming months, the Scottish government will publish a series of papers making a detailed case for independence, as well as bringing together a new constitutional convention – similar to that which paved the way for the Scottish parliament in the 1990s – to build support among civic Scotland.

At the same time, she will ask the Electoral Commission to test the question “should Scotland be an independent country”, which she described as “ the next practical step we need to take within our powers to prepare for a referendum”.

YouGov polling found that Brexit had significantly boosted support for independence, with 21% of those who voted no in the Scottish poll and in favour of remaining in the EU having changed their minds on independence.

Yes support was especially strong among those under 50, with 62% of 18- to 24-year-olds and 67% of 25- to 49-year-olds backing independence, which Sturgeon described as “phenomenal”.

Warning that there was a tendency within the yes movement to act as though people had already been persuaded, she said: “That job is still to be done. While we are in that war of attrition on the process, we shouldn’t be sitting doing nothing.

“If I thought there was an easier way I’d have taken it. That’s the reality. Stay focused, stay united, we are winning and we’ve got to stay the course.”