Ukrainian President Volodymyr Zelensky made a surprise visit to Saudi Arabia on Thursday, with plans to sign a new air security agreement.

• The deal focuses on "security cooperation -- in particular, the protection of the skies".
• Key figures include President Volodymyr Zelensky and officials from Saudi Arabia.
• The visit is partly driven by Gulf countries' interest in Ukraine's expertise in downing Iranian-designed drones, similar to those used against Ukraine.