The UK's Prudential Regulation Authority (PRA) is looking at ways to access more data from Amazon Web Services, Microsoft Azure and Google Cloud amid concern about how important the three have become to the financial services sector, according to the Financial Times.

With FS firms transferring ever-greater amounts of data to the cloud giants, the Bank of England's PRA is concerned about the effects of outages and cyberattacks, says the FT, citing sources.

“We are looking at cloud providers in terms of operational resilience,” a source tells the FT. “Do we need to go further, how can we build confidence in them? We are beginning to see them as important third parties who need more oversight.”

In July, the BofE warned that additional policy measures may be required to mitigate financial stability risks from the growing concentration of power in the hands of global cloud providers. In its bi-annual Financial Stability Report, the central bank singled out the 'secretive' practices and opaque nature of major cloud providers such as Google, Amazon and Microsoft.

Since then, Amazon Web Services has suffered a serious outage that affected a host of big firms, prompting serious worries at regulators around the world. The PRA is looking into how to deal with a situation in which AWS and Azure fail at the same time.