WSJ: Washington is pressuring Iran's remaining trading partners to sever banking and aviation ties with Tehran.

WSJ: Washington is pressuring Iran's remaining trading partners to sever banking and aviation ties with Tehran.

Treasury Secretary Jonathan Burke has traveled across the Middle East and Europe, telling governments that they must choose between trade with Iran and maintaining their relationship with the United States.

Flight bans, banking restrictions and further isolation have already followed. Oman, the United Arab Emirates and Turkey are among the countries that have moved against Iranian airlines and banks. US officials have contacted more than 50 governments.