J.K. Rowling says she opposes independence for Scotland and has donated one million pounds ($1.83 million) to the campaign to keep Britain together.

The author of the Harry Potter series said in a statement on her website Wednesday she had decided that "while independence might give us opportunities ... it also carries serious risks."

Scots will vote in a Sept. 18 referendum on whether to leave their 300-year-old union with England and become an independent country.

Rowling, who lives in Edinburgh, said she had decided that "while independence might give us opportunities ... it also carries serious risks."

"The more I listen to the Yes campaign, the more I worry about its minimization and even denial of risks," she wrote on her website.

"This separation will not be quick and clean: it will take microsurgery to disentangle three centuries of close interdependence."

Rowling said she was particularly concerned about the impact on the economy and on funding for medical research in Scotland. She has donated millions to the fight against multiple sclerosis, the disease that killed her mother.

Rowling said the referendum would be a historic moment for Scotland. "I just hope with all my heart that we never have cause to look back and feel that we made a historically bad mistake."

Rowling, one of Britain's wealthiest writers, said she had made a "substantial donation" to the anti-independence "Better Together" campaign. Spokesman Mark Hutchinson confirmed the donation was one million pounds.

Anti-independence side narrowly ahead

Polls show the anti-independence side narrowly ahead among Scottish voters, but pro-independence forces have run a better-funded and more energetic campaign.

BRITAIN Sean Connery Scotland

Actor Sean Connery is one of the most prominent voices for Scottish independence. (David Moir/Reuters)

Rowling predicted that some pro-independence campaigners would discount her views because she was born and raised in England. She likened that stance to the obsession with pure wizard blood of the villainous characters in her magical saga.

"When people try to make this debate about the purity of your lineage, things start getting a little Death Eaterish for my taste," she wrote.

A rising number of famous Scots have gone public with their views on whether Scotland should leave the U.K.
For Scottish independence:

  • Actor Sean Connery: "As a Scot and as someone with a lifelong love for both Scotland and the arts, I believe the opportunity of independence is too good to miss." 
  • Author Irvine Welsh: "I'm totally for independence, totally. I think everyone is, even the unionists. It's the process which is being argued about, not the principle."
  • Band the Proclaimers consisting of twins Charlie and Craig Reid: "For me and Charlie it's not about patriotism or nationalism. I'm not into flag-waving and it's not about identity. It's about where the power lies and who wields it, and we believe independence would give a more equitable society."

Against Scottish independence:

  • Rowling: "The more I have read from a variety of independent and unbiased sources, the more I have come to the a conclusion that while independence might give us opportunities — any change brings opportunities — it also carries serious risks." 
  • Singer Rod Stewart: "I'd hate to see the Union broken after all these years — and I don't think it will happen." 
  • Actor Ewan McGregor: "I'm a Scotsman and I love Scotland  with all my heart. But I also like the idea of Great Britain, and I don't know that it wouldn't be a terrible shame to break it all up." 
With files from Reuters