China said it is “gravely concerned” about President Donald Trump‘s ambitious Golden Dome project, and warned that it could upset the global strategic balance.

On Tuesday, Trump announced the Golden Dome project — a concept initially pitched during his campaign that reflects Israel’s Iron Dome but is now more analogous to former President Ronald Reagan’s Strategic Defense Initiative, better known as Star Wars. Trump explicitly drew connections to Reagan’s project in his Tuesday presentation, leading some analysts to describe the project as “Star Wars on steroids.”