Moody's May Downgrade UBS and Morgan Stanley

It was reviewing the long-term ratings and standalone credit assessments of a range of banks, Moody's added. Markets were unaffected by the Moody's announcement.

"Capital markets firms are confronting evolving challenges, such as more fragile funding conditions, wider credit spreads, increased regulatory burdens and more difficult operating conditions," the ratings agency said in a statement.

It said among 17 banks and securities firms with global capital markets operations, it might cut the long-term credit rating of UBS, Credit Suisse and Morgan Stanley by as much as three notches following the review. It said the guidance was indicative.

Among the banks that might be downgraded by two notches are Barclays, BNP Paribas, Credit Agricole, Deutsche Bank, HSBC Holdings, and Goldman Sachs.

Bank of America and Nomura were included in those that might be downgraded by one notch.

The U.S. rating agency said in a separate statement its action on 114 financial institutions from 16 European nations reflected the impact of the debt crisis and deteriorating creditworthiness of its governments.

It cited more fragile funding conditions, increased regulatory burdens and a tougher economic environment for its review of banks and securities firms with global reach.

Last Monday, Moody's cut the ratings of six European nations including Italy, Spain and Portugal and warned it could strip France, Britain and Austria of their top-level AAA grade.

Standard & Poor's cut France's and Austria's top ratings and downgraded seven other euro zone nations last month. It also cut the euro zone's bailout fund by one notch.

Moody's on Thursday also downgraded the insurance financial strength ratings (IFSR) by one or two notches of several insurance companies, which it said related to their investment and operating exposures to Spain and Italy.

These included Unipol Assicurazioni SpA, Mapfre Global Risks, Assicurazioni Generali SpA and Allianz SpA. It affirmed the IFSR of Allianz SE, AXA SA, Aviva Plc and their subsidiaries, but cut the outlook on the rating to negative from stable.  Read more.