UK Government “scared” to allow indyref because it will lose claims SNP Deputy leader
With no prospect of that consent Nicola Sturgeon announced she will press ahead with plans to treat the next national poll - likely a general election - as a de facto referendum.
Speaking to the BBC on Sunday, Mr Brown said the UK Government fears it could lose Scotland and warned the decision will see the Yes movement reach "new heights", claiming it will only fuel the demand for independence.
He claimed the Supreme Court ruling "shattered forever the notion of the UK as a voluntary union of nations".
"I think they know they're going to lose this, that's why they are doing everything they can to twist democracy, to refuse the opportunity for the people of Scotland, because they know they're going to lose," he told the Sunday Show.
"(The UK Government are) scared, that's the point," he added.
But Mr Brown moved away from talk of using the subsequent election as a de facto referendum, which had been posited by SNP MP Angus MacNeil following the Supreme Court ruling.
To force a Holyrood election, two-thirds of MSPs would have to vote in favour or the post of first minister would have to be vacant for 28 days.
Mr Brown said: "We do want to have a referendum next year, and we could do that still if the UK Government just agreed to the proper route they've agreed in the past.
"That's the reasonable way to do it, that's the democratic way to do it."
First Minister Ms Sturgeon has said she is willing to speak to Prime Minister Rishi Sunak about the possibility of a Section 30 order which would grant Holyrood the necessary powers to stage a vote.
Mr Brown wouldn’t comment on how the votes of other parties would impact the SNP's independence mandate.
He pointed to a snap poll by Find Out Now for Channel 4 of 1,006 Scots, which suggested 51 per cent would vote for the SNP if they knew their vote would be used to negotiate independence.
The Scottish Greens have said any vote for them in a de facto referendum is a vote for independence. But former Green MSP Andy Wightman hit back at Sturgeon following her calls for a de facto referendum at the next general elections.
Mr Brown added: "It also laid bare the duplicity of the Westminster parties who are flagrantly breaching their own pledges to the people to respect Scottish democracy.
"But if those same parties think that this week has ended the debate on Scotland's future, they couldn't be more mistaken.
"It is a movement which will hit new heights by galvanising public opinion in every city, town, village and community the length and breadth of the country."