The SNP leader and Scottish First Minister said following last week's election victory in which her party took 47 of the 59 Scottish seats at Westminster, the case for another referendum was "unarguable".
Today she launched a 38-page document entitled "Scotland's Right to Choose", and announced that not only would she ask for a Section 30 Order - the time-limited transfer of powers to hold a referendum next year - but that the Scotland Act should be permanently changed so future Scottish Government would no longer have to seek Westminster's permission for a vote.
However she said she was "open to negotiation" on the issue.
The move comes as a Yougov poll this week showed that 48 per cent of respondents from across the UK as a whole were against the idea of a second Scottish independence referendum, while 46 per cent of respondents north of the Border were in favour, though no date was specified.
A summary attached to the SNP's document also said: "The Scottish Government also believes that when the people of Scotland are invited to make a choice about their future, they should do so understanding what the consequences of their vote would be; and with a guarantee that any vote to become independent would be respected and acted upon by the UK Government."
A summary released ahead of Ms Sturgeon's speech at Bute House made a pointed declaration about the Union, describing it as "voluntary association of nations", and stressing that as such "it must be open to any of its parts democratically to choose to withdraw from the Union".
Speaking at Bute House, her official residence in Edinburgh, Ms Sturgeon said: "The alternative is a future that we have rejected being imposed upon us. Scotland made it very clear last week it does not want a Tory government led by Boris Johnson taking us out of the European Union.
"That is the future we face if we do not have the opportunity to consider the alternative of independence."
The Prime Minister has repeatedly made clear his opposition to Scotland having a second independence referendum, and it is understood that will be reiterated in today's Queen's Speech in the House of Commons.
Asked what her response will be when Boris Johnson says no, as he has pledged, Ms Sturgeon said that question should be turned on its head. "It is for the Prime Minister to defend why he believes that the UK is not a voluntary union of equal nations," she said.
"it is for the Prime Minister to set out why he does not believe the people in Scotland have the right to self-determination, it is for the Prime Minister to explain why he believes it is acceptable to ignore election after election in Scotland and over-ride a democratic mandate stronger than the one he claims for his Brexit deal."
She added: "The Conservatives only response to this so far has been the referendum result in 2014, they use that result to justify doing whatever they want to Scotland no matter what people here think, and no matter how much damage they cause to people's lives. The Tories are in effect saying that democracy in Scotland stopped the day we voted no in 2014, and that cannot and will not hold.
"In 2014 a majority of people did vote no to independence, but in 2016 an overwhelming majority voted to remain in the EU, despite that, in a matter of weeks the Tories intend to remove Scotland from the EU. The future that the people of Scotland chose is no longer available to them."
Ms Sturgeon insisted: "It is a fundamental democratic principle that decisions on Scotland's constitutional future should rest with the people who live here.
"As this document lays out, the Scottish Government has a clear democratic mandate to offer people a choice on that future in an independence referendum, and the UK Government has a democratic duty to recognise that. Last week's general election has only strengthened that mandate."
Responding to Ms Sturgeon's remarks, Scottish Conservative interim leader Jackson Carlaw said: “Nicola Sturgeon hasn’t said anything new here, and the fundamentals remain the same.
“Scotland voted No in 2014, and both sides agreed that would be a once-in-a-generation decision come what may. Ever since then Nicola Sturgeon has tried to bend the rules, and this latest stunt is another example of that.
“Now, more than ever, Scotland needs a government that cares about public services, jobs and the economy. Instead, it’s got an SNP First Minister who’s only serious about breaking up the country.
“Nicola Sturgeon has made it clear again if she doesn’t win indyref2, it’ll be straight onto indyref3 and indyref4. She wants to trap Scotland in a neverendum when most people simply want to move on.”
And Scottish Liberal Democrat leader Willie Rennie said: “Even with Boris Johnson as her recruiting sergeant, the nationalists still failed to get 50 per cent of those who turned out to vote to back them, never mind the population as a whole.
“You could drive a truck through the holes in Nicola Sturgeon’s case for independence. She still can’t say for sure what currency she would use, whether there will be a hard border with England or what she will do about the decade of spending cuts her own growth commission say it would require.
“Our message to the SNP is clear, stop neglecting mental health, education and policing and get back to the day job.”
However pro-independence Scottish Greens co-leader Patrick Harvie supported the First Minister and said: “The Scottish Parliament has already voted to seek a section 30 order, and if Nicola Sturgeon feels the need to bring another vote to Holyrood, the Scottish Greens will back it again.
“If Boris Johnson ignores that mandate, as he is threatening to do, it will only strengthen the case for Scotland to break ties with a flawed democracy that denies us a say over our future.
"His reckless Brexit cuts our ties with Europe, rips up workers rights and environmental protections and pursues a right wing race to the bottom in order to get a US trade deal.
“It’s only right that Scotland gets the option to decide a different future during the transition period.”
The pro-UK campaign group Scotland in Union today launched a new campaign, Scotland Deserves Better, in the wake of Nicola Sturgeon’s speech. It has published a petition calling on the SNP government to drop its demand for a Section 30 order.
Pamela Nash, chief executive of Scotland in Union, said: “It is clearer than ever that the SNP only cares about one thing: breaking up Britain. The SNP’s obsession with independence has come at the cost of our public services.
“Every minute and every pound spent on pursuing another Scexit referendum is time and money taken away from fixing our public services, improving our economy and ultimately the quality of life of Scots. Scotland deserves better.
“The SNP should drop its demand for a Section 30 order and instead focus exclusively on the current devolved responsibilities of the Scottish Government including health and education. It’s time for Nicola Sturgeon to do her job.”