From the Document: "The State of Qatar has employed its ample financial resources to exert regional influence separate from and independent of Saudi Arabia, the de facto leader of the Gulf Cooperation Council (GCC: Saudi Arabia, Kuwait, Qatar, United Arab Emirates, Bahrain, and Oman), an alliance of six Gulf monarchies. While fostering a close defense and security alliance with the United States, Qatar has intervened in several regional conflicts and has, at times, engaged Sunni Islamists, Iran and Iran-backed groups, and Israeli officials. Qatar has maintained consistent dialogue with Iran while also supporting U.S. efforts to limit Iran's regional influence and U.S. combat against major regional terrorist organizations such as the Islamic State organization."
CRS Report for Congress, R44533
Congressional Research Service: https://crsreports.congress.gov/