Royal Bank of Scotland (RBS) and Lloyds Banking Group could be forced to shift their business operations to England, if Scotland became independent.
With most of their UK operations in England, Wales and Northern Ireland, RBS and Lloyds are the two biggest Scottish-domiciled companies by assets, reported Financial Times.
According to a BBC report, an EU law which is designed to ensure banks are regulated in the country where they have most of their operations, could play a major role in deciding the future of the banks.
Lloyds said that it was examining the EU law that could force it to shift its legal domicile to London if the Scottish-Yes vote won.
Meanwhile, in its annual report Lloyds cautioned that Scottish independence could "have a material impact on compliance costs, the tax position, and costs of funding for the group."
RBS, which employs more than 12,000 people in Scotland, did not comment.

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