Large bank transfers, including some house purchases, have been delayed by a "global payments issue" hitting the Bank of England's Chaps bank transfer system today.
The BoE said some "high value and time-sensitive" payments were affected. It said there has not been any effect for retail payment systems.
"We are mindful of the impact this is likely to have and are working closely with a third party supplier, industry and other authorities to resolve the issue as promptly as possible," the BoE said in a statement.
"If you are concerned about a Chaps payment you plan to make or receive today, please contact your bank, or other payment service provider."
As retail payments had not been hit, the Bank said "people and businesses can continue to use cash points, card payments and bank transfers as normal".
The Financial Times reported that the issue originated from the Swift international payments system, though the sources said this was not caused by a cyber attack.
Chaps is an automated same-day system used to settle high-value wholesale payments between high-street banks and some international banks, as well as time-critical payments such as buying, or paying a deposit on, a property.
The system is usually open from 6am to 6pm, Monday to Friday, excluding bank or public holidays.
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