U.S. Special Representative for Iran Brian Hook acknowledged the challenge ahead on ending the crisis that's torn apart the Gulf Cooperation Council, with Bahrain, Saudi Arabia and the United Arab Emirates part of the boycott that's targeted fellow member Qatar since June 2017.

The six Arab countries who last month cut ties with Qatar are reported to have reminded FIFA that they consider the Gulf state to be a "base of terrorism."

Four Arab countries which cut ties with Qatar over its alleged support of terrorism on Friday designated dozens of people with alleged links to Qatar as terrorists.