Another Scottish independence referendum is "highly likely", Nicola Sturgeon said after she revealed the Scottish government will begin to prepare the legislation for a fresh vote to break-up the union.
In a hugely significant step, the First Minister of Scotland made clear Scotland voting for Remain - in common with London and Northern Ireland - cleared the way for a repeat of the 2014 ballot.
Sturgeon said it is "democratically unacceptable" that Scotland would be taken out of the EU "against its will", and it will take "all possible steps and explore all options" to stay in the bloc.
"I am proud of Scotland and how we voted yesterday. We proved we are a modern, outward looking, open and inclusive country and we said clearly that we don't want to leave the EU."
She added London Mayor, Sadiq Khan, shared the same view about their areas remaining in EU, saying: "I have also spoken this morning with Sadiq Khan and he is clear that he shares this objective for London, so there is clear common cause between us."
Meanwhile, Irish republicans are calling for the reunification of Ireland after Britain voted to leave the European Union.
London’s secession from the post-Brexit UK gained some credence, with people seriously talking up the city’s eight million people living in a newly-independent city state within the EU.
Labour’s Lord Livermore, who campaigned for Britain to stay in the EU, tweeted that London’s independence “should be a goal”, saying there is the city would have twice the GDP of fellow city state Singapore.
London Mayor Sadiq Khan sent a message to “every European resident living in London - you are very welcome here”.
In Northern Ireland, Sinn Fein's Martin McGuinness, Deputy First Minister, called for a vote to leave the UK and unite with Ireland - which is in the EU.
"The British government now has no democratic mandate to represent the views of the North in any future negotiations with the European Union, and I do believe that there is a democratic imperative for a 'border poll' to be held," he said.
She said: "As things stand, Scotland faces the prospect of being taken out of the EU against our will. I regard that as democratically unacceptable."
The First Minister said it is now "highly likely" that there will another vote on Scotland's place in the UK in the next two years.
Speaking at her official residence, Bute House in Edinburgh, she said: "I intend to take all possible steps and explore all possible options to give effect to how people in Scotland voted - in other words to secure our continuing place in the EU, and in the single market in particular."
The SNP manifesto for May's Holyrood elections said the Scottish Parliament "should have the right to hold another referendum if there is a significant and material change in the circumstances that prevailed in 2014, such as Scotland being taken out of the EU against our will".
She said: "As things stand, Scotland faces the prospect of being taken out of the EU against our will. I regard that as democratically unacceptable."
The First Minister said it is now "highly likely" that there will another vote on Scotland's place in the UK in the next two years.
Speaking at her official residence, Bute House in Edinburgh, she said: "I intend to take all possible steps and explore all possible options to give effect to how people in Scotland voted - in other words to secure our continuing place in the EU, and in the single market in particular."
The SNP manifesto for May's Holyrood elections said the Scottish Parliament "should have the right to hold another referendum if there is a significant and material change in the circumstances that prevailed in 2014, such as Scotland being taken out of the EU against our will".
Ms Sturgeon said: "It is, therefore, a statement of the obvious that a second referendum must be on the table, and it is on the table."
All 32 local authority areas north of the border returned a majority for Remain in the EU referendum, with the country voting by 62% to 38% in favour of Remain.
Ms Sturgeon said: "Unfortunately, of course, yesterday's result in Scotland was not echoed across the whole of the United Kingdom. The UK-wide vote to leave the EU is one that I deeply regret.
"The vote across England and Wales was a rejection of the EU and it was a sign of divergence between Scotland and large parts of the rest of the UK and how we see our place in the rest of the world."
The Scottish Government's resilience committee, which meets in times of emergency, is due to meet this afternoon, Ms Sturgeon said.
Ministers will seek "direct discussions" with EU institutions and member states, with Ms Sturgeon saying she would "make clear that Scotland has voted to stay in the EU and I intend to discuss all options for doing so".
The Scottish Cabinet will meet on Saturday while the First Minister will make a statement to MSPs at Holyrood on Tuesday.
Ms Sturgeon stressed, however, there are "many discussions to be had before final decisions can be taken" and said: "It would not be right to rush to judgements ahead to discussions on how Scotland's result will be responded to by the EU."
She went on to state that when the UK Government triggers the Article 50 process to withdraw from Europe, "the UK will be on a two-year path to the EU exit door".
The SNP leader added: "If Parliament judges that a second referendum is the best or only way to protect our place in Europe, it must have the option to hold one within that timescale.
"That means we must act now to protect that position.
"I can therefore confirm today in order to protect that position we will begin to prepare the legislation that will be required to enable a new independence referendum to take place if and when Parliament so decides."
After having campaigned for a Remain vote, Ms Sturgeon said: "This is not a situation that I wanted Scotland or the UK to be in today.
"The issues we face are complex. There are many people who voted against independence in 2014 who are today reassessing their decision, indeed a very large number of them have contacted me already.
"My priority in the days, weeks and months ahead will be to act at all times in the best interests of Scotland and in a way that unites not divides us."
She insisted: "I am proud of Scotland and how we voted yesterday.
"We proved we are a modern, outward-looking, open and inclusive country, and we said clearly that we do not want to leave the Euroepan Union.
"I am determined that we will do what it takes to make sure that these aspirations are realised."
Answering questions from journalists, Ms Sturgeon said a second vote on independence "is now highly likely" but added: "I also think it's important that we take time to consider all steps and to have the discussions, not least to assess the response of the European Union to the vote that Scotland expressed yesterday.
"I am absolutely determined in my responsibility to give effect to how Scotland voted yesterday and it's important that I take all steps to make sure that we explore all options to do exactly that."
Ms Sturgeon was also questioned on whether she was confident that Scots would back independence amidst the potential turmoil of a Brexit vote.
She responded: "It is exactly because of the uncertainty and the potential turmoil that we face that I think it is in my responsibility to seek to bring Scotland together, to lead Scotland forward into a position that allows us to continue with the stability and the certainty that membership of the EU gives us.
"I'm not saying that these issues are straightforward but I do think that is the responsibility, and indeed the opportunity, that now lies before us."
Pressed on what level of public support she would like to see before another referendum on independence is held, she replied: "My guiding principle in every decision I take over these next days, weeks and months will be what I judge to be in the best interests not of the SNP or as me as First Minister, but what I judge to be in the best interests of Scotland. That's the responsibility I have and that's how I will guide every decision I will take."