Ukrainian President Volodymyr Zelensky made a surprise visit to Saudi Arabia on Thursday amid a wider effort to lend Ukraine’s drone defense expertise to the U.S. and Gulf States.

Zelensky had offered his country’s expertise in defense against kamikaze drone attacks, cultivated in its grinding war against Russia, just days after the war began. These promised personnel arrived in the Middle East recently, with Zelensky saying last week that 201 personnel had been deployed, and another 34 were on their way.