Some of the UK 's largest banks have been downgraded by the credit agency Moody's.
Royal Bank of Scotland (RBS), Barclays and HSBC have all been downgraded, while Lloyds has also had its rating cut.
It comes as moody's has announced the downgrading of 15 major financial institutions, including Bank of America, Citigroup, Morgan Stanley, UBS and Credit Suisse.
HSBC, RBS and Lloyds have had their ratings cut by one notch, while Barclays has had its rating cut by two notches.
The downgrades could potentially make borrowing more expensive for the banks, which could be compounded if other credit agencies follow Moody's lead.
RBS hit back at the downgrade, saying in a statement: "The Group disagrees with Moody's ratings change which the Group feels is backward-looking and does not give adequate credit for the substantial improvements the Group has made to its balance sheet, funding and risk profile."
The bank added that the downgrade will cost the bank some £9 billion in funds to cover its debts.
Its share price dipped by 1.2% in this morning's trading as the markets reacted to the news, while Barclays saw 0.6% shaved off its value.
Richard Lloyd, executive director of Which? said that those worried by the downgrades should make sure their savings are protected.
"The exact impact this credit rating downgrade will have on consumers is uncertain but there are steps people can take to protect their money," he commented.
"People should spread their money across different banks and make sure their cash is in an account covered by the UK compensation scheme, which guarantees savings up to £85,000 per person, per financial institution."
Find out where your bank or building society is licensed, and what deposit protection guarantees you'll get if they go bust (includes UK Crown dependencies).
Have your say - Do you think home owners and businesses face the prospect of higher interest rates?
Disclaimer: Information is correct as of the date of publication (shown at the top of this article). Any products featured may be withdrawn by their provider or changed at any time.
Moneyfacts.co.uk will, like most other websites, place cookies onto your computer’s
hard drive. This includes tracking cookies.