The Trump administration has expanded the power of adviser Elon Musk's government-cutting team over the State Department, making a Musk lieutenant acting head of foreign assistance.

A senior US official confirmed the new job for Jeremy Lewin, an associate of the Department of Government Efficiency earlier appointed to help finish dismantling the US Agency for International Development. The official was not authorized to comment publicly on a personnel matter and spoke on condition of anonymity.

The move comes as President Donald Trump's administration is pushing to greatly reduce what in 2024 was $52 billion in humanitarian, health and development programs overseas by the State Department and USAID. Lewin's appointment gives Musk's team, which has worked with the Republican administration to make deep cuts to government programs and services, one of its highest formal positions in the federal government.

Lewin's appointment follows the departure of a Trump political appointee, Pete Marocco, as the administration's head of foreign assistance. State officials credited Marocco with helping oversee the elimination of staff, programs and funding at USAID. Marocco reportedly clashed with Secretary of State Marco Rubio and others in the administration and Congress.

On Tuesday, Rubio said he had canceled 139 additional foreign assistance grants worth USD 214 million, including for programs he described as “misguided," including Building the Migrant Domestic Worker-Led Movement' in Lebanon and Get the Trolls Out!' in Great Britain.

“We are cleaning up the mess the previous administration left and rebuilding an agency that's focused on putting America first,” Rubio said in a post on X.

The Trump administration and DOGE have been slashing jobs and funding across the federal government, and a preliminary proposal for some of the latest cuts is targeting the State Department.

The White House's Office of Management and Budget has proposed gutting the State Department budget by almost 50 per cent, closing a number of overseas diplomatic missions, slashing the number of diplomatic staff, and eliminating funding for nearly all international organizations, including the United Nations, many of its agencies and NATO headquarters.

The proposal, which was presented to the State Department last week and is still in a highly preliminary phase, is not expected to pass muster with either the department's leadership or Congress.

Officials familiar with the proposal say it must still go through several rounds of review before it even gets to lawmakers, who in the past have amended and even rejected White House budget requests.