The downgrade on Thursday of 15 major international banks and securities firms by Moody’s Investors Service is “absurd” as the financial health of these institutions is at the best it has been in years, one analyst tells CNBC.

“This is one of the most absurd things that Moody’s has ever done perhaps in the history of the company,” said Dick Bove, Vice President of Equity Research in the Financial Sector at Connecticut-based Rochdale Securities.