President Donald Trump saw off billionaire Elon Musk in the Oval Office on Friday as Musk concluded his stint as a government adviser to the president and head of the Department of Government Efficiency.

President Trump said Musk had headed up "the most sweeping and consequential" reforms to government scope, and promised to keep them in place.

"We are totally committed to making the DOGE cuts permanent," the president said.

At the head of DOGE, Musk initially sought to eliminate $2 trillion in wasteful government spending, and later revised that target down to $1 trillion and then to $150 billion. The program has so far fallen far short of that goal. By some of its own internal estimates DOGE has delivered less than $30 billion in savings.

Analysis of DOGE's contract cancellations showed many were expected to deliver no savings, often because the government was legally compelled to pay out their costs.

DOGE has stripped regulations from dozens of agencies, affecting consumer financial protections, utility fees, health insurance and appliance standards.

It has made high-profile agency cuts, including by shuttering USAID, which officials estimate may lead to hundreds of thousands of deaths from malnutrition and disease worldwide.

Speaking in the Oval Office Friday, Musk promised the group's mission would continue.

"The DOGE team will only grow stronger over time. The DOGE influence will only grow stronger," Musk said. "It is permeating throughout the government, and I'm confident that over time, we will see a trillion dollars of savings and reduction — a trillion dollars of waste and fraud reduction."

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President Trump said Musk would maintain some level of informal involvement in his administration. DOGE employees would keep working within government agencies, he said, and Musk himself would "be back and forth, I imagine."

Musk said he would continue to "be a friend and adviser to the president."

President Trump presented Musk with a golden key to commemorate his work at DOGE.