WASHINGTON (AP) — President Donald Trump has bestowed a top U.S. honor on Kuwait’s ruling emir, who has played a central role in resolving a yearslong four-nation boycott of Qatar and is now ill and receiving treatment in the U.S., the White House said Friday.

Trump awarded the Legion of Merit to Kuwait’s Sheikh Sabah Al Ahmad Al Sabah, who, along with Oman, has sought dialog to end the dispute that has torn apart the Gulf Cooperation Council.

Bahrain, Saudi Arabia and the United Arab Emirates have been part of the boycott that’s targeted fellow GCC member Qatar since June 2017. Egypt also joined the boycott, which saw nations close their airspace and borders to Qatar.

“A leader in the Middle East for decades, the emir has been a truly unwavering friend and partner to the United States,” the White House said in a statement. “The emir is also an unparalleled diplomat, having served as his nation’s foreign minister for 40 years. His tireless mediation of disputes in the Middle East has bridged divides under the most challenging circumstances.”

The Legion of Merit is a rarely awarded decoration that can only be bestowed by the president, typically to chiefs of state or heads of government of other countries. The honor was last awarded in 1991.

The emir’s eldest son, Sheikh Nasser bin Sabah Al Ahmad Al Sabah of the State of Kuwait, was to accept the award on behalf of the emir in a private ceremony.

In July, Sheikh Sabah flew across the world in a U.S. Air Force C-17 flying hospital, just days after undergoing an unspecified surgery at home. The dramatic airlift to the Mayo Clinic reflected the close ties between the two nations but also raised concerns over the ruler’s medical condition. The clinic declined to discuss his condition on Friday.