I think it's not a clandestine operation but just a challenge to the US demands, therefore it's public?
US: Don't trade with Iran because politics
UK, DE, FR, CN, RU: Sorry, We like the deal we made and we would like to trade with Iran.
US: If any company trades with Iran, won't be able to trade with the USA. Make your choise.
UK, DE, FR, CN, RU: Okay then, we will create an infrastructure where the USA won't be able to legally identify and sanction our companies that trade with Iran.
US: Don't trade with Iran because politics
UK, DE, FR, CN, RU: Sorry, We like the deal we made and we would like to trade with Iran.
US: If any company trades with Iran, won't be able to trade with the USA. Make your choise.
UK, DE, FR, CN, RU: Okay then, we will create an infrastructure where the USA won't be able to legally identify and sanction our companies that trade with Iran.