WASHINGTON: Billionaire Elon Musk's role in the Trump administration is as a White House employee and senior adviser to the president, and is not an employee of the Department of Government Efficiency (DOGE) and has no decision-making authority, the White House said in a court filing on Monday.

According to a filing signed by Joshua Fisher, director of the Office of Administration at the White House, Musk can only advise the president and communicate the president's directives.

"Like other senior White House advisors, Mr Musk has no actual or formal authority to make government decisions himself," it said.

Fisher's filing, made in a case brought against Musk by the State of New Mexico, said that Musk was not an employee of the U.S. DOGE Service, or the U.S. DOGE Service Temporary Organization, and added: "Mr Musk is not the U.S. DOGE Service Administrator."

DOGE has swept through federal agencies since Donald Trump began his second term as president last month and put Musk, the chief executive of carmaker Tesla, in charge of rooting out wasteful spending as part a dramatic overhaul of government that has included thousands of job cuts.