Honda Motor Co. is among the world's biggest companies that disclose little or no financial details about their operations abroad, according to a report by Transparency International, which also singled out Chinese companies and pointed to U.S. tech giants like Amazon.com Inc. and Google Inc. as well.

The Berlin-based anti-corruption watchdog named Honda, Bank of China Ltd., Bank of Communications Co., Agricultural Bank of China Ltd. and Sberbank of Russia as the five least transparent companies.

Bank of China could not be reached for comment on the report. The other four companies declined to comment.