The First Minister was emphatic she would not consider such a move. She said any independence referendum would need to have the same legal basis as the vote in 2014.
Her comments were seen as slapping down Mr Brown, who had been filmed telling independence activists “if we want to have a referendum, then we decide we’re going to have a referendum”.
And they came just a few hours after Foreign Secretary Jeremy Hunt ruled out the granting of a Section 30 order by his government.
Asked at an event in Glasgow if Prime Minister Theresa May should say “yes” or “no” if the Scottish Government seeks permission for a second independence referendum, Mr Hunt said: “I can tell you the answer to that very simply – the answer of course will be no.”
Mr Brown’s remarks highlight the pressure on Ms Sturgeon from the grassroots of her party and the independence movement, who are impatient for another vote in the light of Scotland’s impending departure from the EU as part of the UK’s Brexit vote.
Mr Brown, who is the SNP’s campaigns manager, was filmed saying: “So, now I have said … that I don’t think certainly the SNP, and I don’t think the Yes movement, should be willing to anticipate a refusal of a Section 30 order as a reason not to call a referendum. If we want to have a referendum, then we decide we’re going to have a referendum.”
Attempting later to clarify his position on social media, he said: “My position is clear – the deeply undemocratic stance of the UK government in denying the mandate for indyref and refusing a Section 30 order should not prevent the Scottish Government seeking one and planning on the basis of winning that case.”
The issue was also raised in yesterday’s First Minister’s Questions by interim Scottish Conservative leader Jackson Carlaw, who suggested the SNP was intent on launching “an illegal referendum within a matter of weeks”.
While the Scottish Government could stage another vote, a Section 30 order transferring the powers needed to hold such a ballot from Westminster would be needed for it to be legally binding.
The SNP says its 2016 Holyrood manifesto gives them the right to hold another vote as it included a commitment that another referendum could be held if there was a significant change in circumstances from 2014, such as Scotland being taken out of the European Union against the wishes of voters.
At Holyrood, Mr Carlaw asked Ms Sturgeon if she agreed with her “errant deputy”. He said: “There is no majority support for a second independence referendum. And today we read that the First Minister’s deputy is plotting another referendum on independence whether it is legal or not. Another referendum is the last thing Scotland needs. Will she rule out this divisive plan?”
Ms Sturgeon said the legal basis for any future referendum should be “the same” as for the 2014 vote – where the Edinburgh Agreement struck between the Scottish and UK governments set out the conditions for a legally binding ballot.
She said: “The legal basis should be the same as the basis for the last referendum. The only reason we’re talking about this is the disgracefully undemocratic stance of the Conservatives who refuse to recognise the mandate of not just one election, but two elections and endorsed by this Parliament.”
Ms Sturgeon added: “The people of Scotland will have ample opportunity to talk about the many benefits of independence … but can I bring him back to the here and now. Three weeks tomorrow this country is due to be taken out of EU against its will and we still don’t know what will follow from that.”
Asked later by reporters if it was a possibility she could hold a Catalan-style referendum without the permission of Westminster, the First Minister said: “No, I am not open to that possibility.”
Ms Sturgeon has pledged to make a statement on her plans to stage a second referendum on Scottish independence before Brexit day on 29 March. It is expected to be an address to MSPs at Holyrood.
On the “no” position regarding a second Scottish independence referendum, Mr Hunt said: “The answer of course would be no for the very simple reason that we think the Scottish Government should be focusing on the concerns of Scottish voters, which is not to have another very divisive independence referendum, but to focus on an education system which used to be the envy of the world and standards are now falling, to focus on long waits in the NHS.
“That’s what Scottish voters want the Scottish Government to focus on.”