The Trump administration has secretly been pressuring the ICC for months now trying to get them to change their fundamental rules so they will NOT prosecute Trump or any of his senior officials for all the war crimes they've been committing. So he's essentially telling them I want you to promise not to prosecute us or else.
"The White House is pressuring the International Criminal Court (ICC) to alter its founding document to prevent it from investigating U.S. President Donald Trump and his senior officials, a U.S. official told Reuters on Wednesday. These threats mark a significant escalation in Trump’s long-time campaign against the world’s war crimes tribunal at a time when legal experts are suggesting that the administration may have violated international law with U.S. military operations against alleged drug boats near Latin America."