Image copyright AP Image caption Ms Rowling was born in south Gloucestershire but has lived in Edinburgh for the past 21 years

Author JK Rowling has made a £1m donation to help fund the campaign against Scottish independence.

The writer of the Harry Potter books, who lives in Edinburgh, has publicly backed the Better Together campaign.

Explaining her decision on her website, Ms Rowling said there was a "denial of risks" within the "Yes" campaign.

She also said there was a "fringe of nationalists who like to demonise anyone who is not blindly and unquestionably pro-independence".

Voters in Scotland will go to the polls on 18 September to decide on their country's future.

They will be asked the "Yes/No" question: "Should Scotland be an independent country?"

Media playback is unsupported on your device Media caption Alex Salmond says JK Rowling can donate money to whatever she pleases after hearing of her £1m donation to the Better Together campaign

In her statement, Ms Rowling, who was born in south Gloucestershire, said she had friends on both sides of the debate, adding that the "Yes" campaign's "romantic outlook strikes a chord with me".

But she added: "My hesitance at embracing independence has nothing to do with lack of belief in Scotland's remarkable people or its achievements.

"The simple truth is that Scotland is subject to the same 21st century pressures as the rest of the world.

"It must compete in the same global markets, defend itself from the same threats and navigate what still feels like a fragile economic recovery.

Image copyright PA Image caption JK Rowling became an international success with her Harry Potter book series

Image copyright Warner Borthers Image caption The Potter books were made into films which have been distributed worldwide

"The more I listen to the 'Yes' campaign, the more I worry about its minimisation and even denial of risks. Whenever the big issues are raised - our heavy reliance on oil revenue if we become independent, what currency we'll use, whether we'll get back into the EU - reasonable questions are drowned out by accusations of 'scaremongering'".

ANALYSIS - James Cook, Scotland Correspondent, BBC News Image copyright Getty Images "JK Rowling's "magic million" to conjure up a vote against independence is not a great surprise. "She is friends with former PM Gordon Brown and his wife Sarah, has previously donated money to the Labour Party, and told the BBC two years ago that she had reservations about independence. "But the author's argument will resonate with many Scots: attracted by a "romantic" ideal of a "fairer, greener, richer and more equal society", but in the end not quite prepared to accept the associated risks. "A second theme of Ms Rowling's web post will also resonate with many: concern about the nature of the debate. "She writes about a "fringe of nationalists" demonising anyone not 'blindly and unquestionably pro-independence'. "Indeed, she has herself received abuse on social media, something senior Yes campaign strategists realise does not help their cause. "Just today First Minister Alex Salmond ordered a special adviser to apologise for briefing against a pro-union mother-of-two who had been attacked online as a "traitor" to her country. "Mr Salmond points out that pro-independence supporters, in particular Lottery winners Chris and Colin Weir, have suffered online abuse too and called for it to stop. "It would be lovely to think that everyone could come to the same conclusion and debate with civility and grace. "Sadly, such dreams probably belong in the realms of romantic fiction."

Image copyright PA Image caption Lottery winners Colin and Chris Weir have given £5.5m to the SNP and the Yes Scotland campaign

Referring to the donation she wrote: "I wanted to write this because I always prefer to explain in my own words why I am supporting a cause and it will be made public shortly that I've made a substantial donation to the Better Together campaign, which advocates keeping Scotland part of the United Kingdom."

Better Together confirmed the donation was received "recently".

Ms Rowling also said: "I also know that there is a fringe of nationalists who like to demonise anyone who is not blindly and unquestionably pro-independence and I suspect, notwithstanding the fact that I've lived in Scotland for 21 years and plan to remain here for the rest of my life, that they might judge me 'insufficiently Scottish' to have a valid view."

Shortly after the author's blog went live, social media was awash with comments.

Edinburgh-based charity, Dignity Project, tweeted: "What a #bitch after we gave her shelter in our city when she was a single mum."

That remark was condemned by both sides of the debate.

Pro-independence supporter Patrick Harvie MSP responded on Twitter: "A comment like that is a disgrace to the Yes cause, and to the cause of social justice."

The charity later claimed its account had been hacked.

Individual donors

According to the latest Sunday Times Rich List, Ms Rowling is estimated to be worth £570m.

Both sides of the independence campaign have now received a number of big individual donations.

Recent Electoral Commission figures showed that Ayrshire Lottery winners Colin and Chris Weir donated £1m to the SNP earlier this year, taking their total donations to the pro-independence cause to £5.5m.

The couple, who have said they are "lifelong supporters of independence", added that the donations had led to them being subjected to "downright nasty" personal attacks.

They won £161m on EuroMillions in 2011 and have also set up a charitable trust to fund good causes.

Four facts on JK Rowling

Twelve publishers rejected Rowling's Harry Potter manuscripts before Bloomsbury editor Barry Cunningham gave her an advance of £1,500. The author lives in Edinburgh with her three children and second husband. Rowling's seventh and final Harry Potter book, Harry Potter and the Deathly Hallows, was one of the fastest-selling books (it has since been surpassed by 50 Shades of Grey). The author's next book - The Silkworm - is due to be released on 19 June, 2014. It is the second in her Cormoran Strike series and is written under her pseudonym Robert Galbraith.

Following news of the donation, First Minister Alex Salmond told the BBC: "JK Rowling's entitled to give money to whatever she pleases and is entitled to express her views.

"When it comes to people in the artistic community, I think the general feeling would be that the substantial majority of them are backing the 'Yes' cause.

"We're now in a period of spending limits and both campaigns are rightly regulated on how much they can spend - I think that's a good thing, because that makes sure we're going to have an equal fight in terms of finance, and it will be then up to the people to decide and make their judgement."

'No thanks'

Speaking on behalf of the Better Together campaign, Labour's shadow Scottish secretary Margaret Curran said Ms Rowling's donation would be put to "good use".

She added: "This is a significant and welcome intervention from one of this country's most talented and successful women. Separation is failing to win support among women and more and more of us are saying No Thanks to Alex Salmond's plan.

"It doesn't take a wizard to work out that Alex Salmond's case for breaking up the UK simply isn't a risk worth taking. The best way to make sure that we can make our country fairer is by working together across the whole of the UK, not putting a barrier between us."