U.S. bank Goldman Sachs Group Inc traders were preparing to take bids on claims against Credit Suisse Group's riskiest bonds, Bloomberg News reported on Sunday, citing people familiar with the matter.

Clients were told in a message late Sunday that the New York-based bank would soon start trading claims in the so-called additional tier 1 bonds, or AT1s, according to the report.

The Swiss lender's additional tier 1 shares with a nominal value of around 16 billion Swiss francs ($17.24 billion) will be written down completely after the Swiss government provided support for UBS' takeover of Credit Suisse.

Goldman did not immediately respond to a Reuters request for comment. (Reporting by Shubhendu Deshmukh in Bengaluru; Editing by Rashmi Aich)