The banks were included in subpoenas sent out by the government, the report said, citing people familiar with the matter.

The requests were sent by the government before the crisis which resulted in Credit Suisse's takeover by UBS, Bloomberg said.

The Justice Department inquiries are to identify which bank employees dealt with sanctioned clients and how those clients were vetted over the past years, according to the report.

Credit Suisse, UBS, and the Justice Department did not immediately respond to Reuters' emailed requests for comment.

(Reporting by Akanksha Khushi in Bengaluru; editing by Jonathan Oatis)