Elon Musk and OpenAI CEO Sam Altman are fighting on X about Stargate, the infrastructure project to build data centers for OpenAI in the U.S.

Elon Musk claimed overnight Tuesday that tech giants OpenAI, Oracle and Softbank don’t have enough money to fulfill their high-profile pledge to invest $500 billion in U.S. AI infrastructure.

Trump tasked Musk with slashing federal spending with the new Department of Government Efficiency. The pair's budding relationship has grown more entwined since Trump won back the White House, but this is one of their most public disagreements to date.