Observed annually on 5 June since 1973, World Environment Day is UNEP's flagship international day and one of the world's largest platforms for environmental outreach. Each year it brings governments, businesses, civil society, and communities together around the environmental issues that matter most — reaching millions of people around the world.In 2027, the Republic of Serbia will host World Environment Day in Belgrade on 5 June, alongside Expo 2027, themed "Play for Humanity: Sport and Music for All."United Nations Environment Programme (UNEP) is inviting Member States to submit expressions of interest to host the global observance of World Environment Day in 2028 or 2029.Hosting World Environment Day offers countries a unique opportunity to demonstrate leadership on environmental issues, bring its priorities to the global stage, showcase solutions and capture worldwide attention through high-level participation, global media coverage and UNEP’s advocacy campaign, which reaches millions each year.Full details of the call, including host country responsibilities, are available here.