Billionaire Elon Musk arrived on Capitol Hill Tuesday and learned about something new — budget rescissions, an obscure legislative tool that could bring legal heft to his federal budget slashing effort and enshrine the cuts into law. Musk joined a lunch meeting with Republican senators just hours after the Supreme Court issued a setback to the Trump administration's efforts to freeze some $2 billion in foreign aid funds as part of its sweeping shutdown of the U.S. Agency for International Development. As he opened the private session, Musk led with a message urging Congress to act. Over plates of fried catfish, senators explained how the White House could put the billions of dollars of savings he has amassed into what’s called a budget rescissions package, and send it to Congress for a vote to rescind the funding. Musk seemed thrilled, they said. “He was so happy,” said Sen. Lindsey Graham of South Carolina, the Republican chairman of the Senate Budget Committee, who is among those championing the effort. “He didn’t know.” The proposal introduced a potential next phase of his Musk's Department of Government Efficiency efforts and comes at an important time. The Trump administration is fighting in court — and in the court of public opinion — over the budget cuts tearing through the federal government. The Trump administration and Republicans in Congress are eager to show voters that DOGE’s actions are more than headlines of job losses and disruptions, but real savings as Musk’s team roots out waste, fraud and abuse to help reduce the nation’s staggering $2 trillion annual deficit. It also comes as the courts are looking skeptically at the legality of the Trump administration’s actions and as lawmakers’ town halls are being overrun by protesters pushing for answers as tens of thousands of federal workers are being fired. Musk has previously told lawmakers he envisions DOGE can save some $1 trillion in the federal government this year alone.