The UK Government should "do the humane thing" and guarantee the right of EU nationals currently living in the UK to remain, Nicola Sturgeon has insisted.
The First Minister said that while she believes it is "unthinkable" those from EU countries will be asked to leave under Brexit, Prime Minister Theresa May should act now to end the uncertainty facing three million people.
Ms Sturgeon addressed the issue at a special Scottish Cabinet meeting in Edinburgh featuring an audience of EU nationals living in Scotland.
She told them it "breaks her heart" that she is unable to guarantee their futures because immigration is reserved to Westminster.
While the UK Government has repeatedly attempted to reassure EU nationals currently living in the UK, it has yet to rule out the possibility of deportations in the future.
One Italian audience member, Caroline Magoha, spoke of uncertainty over her 13-year-old son's education, adding that he had been bullied at school in the build-up to the EU referendum.
She urged politicians not to make EU nationals from the UK the new "refugees of Europe".
She added: "We have to live with our bags half-packed, our feet halfway out of the door.
"I don't have any trust whatsoever in the Westminster Government. They will wake up one day and say Article 50, EU members, you have to be out within six months. They are capable of that.
"It is inhumane. It is against the basic human rights of children.
"Brexit is ruining the future of Scottish children."
Ms Sturgeon said: "It really breaks my heart that as First Minster, as the elected leader of this country, I am not able to sit here and give you the guarantees and the certainty that you want.
"This is the one that strikes at the heart of humanity. People living here and trying to get on with their lives here should not suddenly have this question mark over their future, and the UK Government could at the stroke of a pen, today if it chose to, put an end to this uncertainty.
"End this uncertainty, end it now, do the humane thing."
She added: "I think it is unthinkable that people living here would be asked to leave. I think the uproar that that would cause, rightly, would be immense.
"But the fact remains that until that commitment is given, people are going to worry and have that uncertainty."
While her remarks were applauded by the audience, Ms Sturgeon was also accused of sowing the seeds of division within the UK by raising the prospect of another independence referendum.
Patrick Harkness, from Northern Ireland, said that while Ms Sturgeon had sought to reassure EU nationals, she was building her own "cold house", while nationalists were "sneering at British people".
He said: "Your backbenchers openly talk about how much people may or may not hate the English and you do not admonish them. Now you're misrepresenting my Remain vote to further yet more separatism.
"First Minister, I think we should recognise that you are building a cold house too. When are you going to hold an event such as this for UK citizens to reassure us that your nationalists will no longer speak division and hatred against us?"
Ms Sturgeon said: "I admonish anybody who is anti-anybody on the basis of their nationality, whatever that nationality may be.
"My belief in Scottish independence never has been and never will be based on a sense of where people come from."
She said she could have called a second independence referendum immediately after the Brexit vote, but had chosen instead to look at all options to secure Scotland's future in Europe.
A UK Government spokesman said: "The Prime Minister has been clear that she wants to protect the status of EU nationals already living here and the only circumstances in which that wouldn't be possible is if British citizens' rights in European member states were not protected in return.
"We are consulting with businesses and other stakeholders across Scotland about the impact of leaving the EU. Those discussions are covering a range of issues, including freedom of movement.
"We are determined to take a 'team UK' approach to leaving the EU, working closely with the Scottish Government and other partners as we form our negotiating strategy, and we will look at any suggestions put forward."