On March 17, Gen. Mark Milley, the chair of the U.S. Joint Chiefs of Staff, and Gen. Valeriy Zaluzhnyi, the leader of Ukraine¡¯s armed forces, dialed into a call to discuss Russia¡¯s invasion of Ukraine. Over the secure line, the two military leaders conferred on air defense systems, real-time battlefield assessments and shared intelligence on Russia¡¯s military losses.

They also talked about Elon Musk.

Zaluzhnyi raised the topic of Starlink, the satellite internet technology made by Musk¡¯s rocket company, SpaceX, three people with knowledge of the conversation said. Ukraine¡¯s battlefield decisions depended on the continued use of Starlink for communications, Zaluzhnyi said, and his country wanted to ensure access and discuss how to cover the cost of the service.