Nicola Sturgeon said that plans to take the UK out of the EU’s single market brought a second Scottish independence referendum “undoubtedly” closer.
The first minister was speaking after Prime Minister Theresa May outlined her government’s thinking on Brexit.
Ms Sturgeon, in a BBC interview, agreed that another vote on independence was “all but inevitable”.
She believed that Scotland should be able to choose a “different future” to the one outlined by Mrs May.
The Scottish government has repeatedly raised the prospect of a vote on independence if Scotland’s membership of the single market was threatened by a so-called hard Brexit.
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It has set out proposals aimed at keeping Scotland in the trade bloc even if the rest of the UK leaves.
Scottish voters backed remaining in the EU by 62% to 38% in last year’s referendum, while the UK as a whole voted to leave.
In an interview with BBC Scotland following the prime minister’s statement, Ms Sturgeon said the move away from the single market “undoubtedly” brings an independence referendum closer.
And when asked by Political Editor Brian Taylor if a second vote was “all but inevitable”, the first minister replied “I think that is very likely the case”.
The first minister said “there comes a point of democratic principle” where if there are to be “fundamental changes” then people should be offered a different choice.
She added: “What I’ve heard today from the PM is an inability to engage in discussions that further compromise.
“I will continue to act in an orderly and reasonable fashion. I said I would exhaust all options, and that’s what I will do. But we are going to have to see some give from the UK government.
“I am not prepared to allow Scotland’s interests to be simply cast aside. I’m not prepared for Scotland to be taken down a path which I firmly believe to be damaging not just to our economy but to the very kind of society that we are.”
The prime minister spoke to Ms Sturgeon ahead of her speech, which confirmed that the UK would leave the single market while seeking the “freest possible trade in goods and services” with the EU after Brexit.
Speaking in London as she outlined her 12 objectives for the Brexit negotiations, Mrs May said the Scottish government’s proposals would be considered as part of the Brexit process.
And she made clear that she wanted a “customs agreement” with the other 27 member states of the EU as part of efforts to ensure Brexit leads to tariff-free trade and “the freest possible trade in goods and services between Britain and the EU’s member states”.
The prime minister also said she wanted the UK to be able to negotiate trade deals with other countries around the world as part of plans to create a “truly global Britain”.
But she added: “What I am proposing cannot mean membership of the single market. Instead we seek the greatest possible access to it through a new comprehensive, bold and ambitious free trade agreement.
“That agreement may take in elements of current single-market arrangements in certain areas.”
When Mrs May’s spokeswoman was asked later if there was still scope for Scotland to stay in the single market, she replied: “The PM was very clear – we are leaving the single market.”
In her speech, the prime minister urged people across the UK to “face the future together, united by what makes us strong”.
Mrs May said: “We will put the preservation of our precious union at the heart of everything we do.
“Because it is only by coming together as one great union of nations and people that we can make the most of the opportunities ahead.”
Mrs May also said she wanted to maintain the common travel area between the UK and Irish Republic, to continue the “practical” sharing of intelligence and policing information with Europe and to take control of the immigration rights for EU citizens in the UK.
And she promised that there would be a vote on the final Brexit deal in both the House of Commons and House of Lords.
The Scottish government led a Holyrood debate on Scotland’s future relationship with Europe on Tuesday afternoon, with MSPs eventually supporting a motion endorsing single market membership.
The motion from Scottish Brexit minister Mike Russell sought to have parliament note the Scottish government’s Brexit plans ahead of talks with the UK government on Thursday.
Backed by 86 members to 36, it also noted “the detrimental social and economic impact on Scotland and the UK of losing their current place in the European single market”.
By endorsing the motion, parliament agreed that “in the event that the UK government opts to leave the single market, alternative approaches within the UK should be sought that would enable Scotland to retain its place within the single market, and the devolution of necessary powers to the Scottish Parliament”.
Speaking ahead of the debate, Scottish Greens MSP Ross Greer said Mrs May’s speech had been “confused, contradictory and dangerous” and made a second independence referendum “look unavoidable”.
But the Scottish Conservatives called on the Scottish government to work with other parts of the UK to get the best possible deal, instead of “continually pitting themselves against the UK government”.
The party’s economy spokesman Dean Lockhart said: “Together, we represent the financial hubs of London, Edinburgh and Glasgow, a significant number of world-class universities and global leadership and expertise across many different sectors.
“With these strengths there can be no doubt that we’ll be in a better position if we negotiate as one team.”
Scottish Labour’s Kezia Dugdale said Mrs May’s speech was “designed to appease the right wing of the Conservative Party”, saying the Tories had “put the union at risk”.
She added that a second independence referendum was “the wrong reaction”, instead calling for constitutional reform including a “new Act of Union”.
And Scottish Lib Dem leader Willie Rennie called for a referendum on the final terms of the Brexit deal, saying he was not going to give up on keeping Scotland in both the EU and the UK.