Washington: US President Donald Trump is moving to cancel nearly $1 billion in spending approved by Congress, targeting funding for immigrant services, diversity initiatives and other programmes through a rare and contested executive power.

The White House announced the move on Friday, with the Office of Management and Budget (OMB) describing the cuts as targeting “the most harmful government spending.”

Most of the funding reductions involve programmes under the Department of Health and Human Services that support refugees and unaccompanied minors accused of being in the country illegally. The administration said the funding was no longer necessary because illegal border crossings had declined considerably.

A White House press release announcing the cuts noted that some of the affected organisations were led by individuals who had served in the administration of former Democratic President Barack Obama.

The decision drew criticism from Republican Senator Susan Collins, who chairs the Senate Appropriations Committee and is facing a tough re-election campaign.

Collins said the administration had acted without warning or consultation. She also pledged to work with colleagues to address what she called “these illegal actions.”

“Not only is the delay itself an impoundment that was not reported to Congress, but also it is a usurpation of Congress’s appropriations powers,” Collins said.

“OMB is an agency of the executive branch. It does not get to decide which programs are worth funding."

Under the usual process, Congress can review a president's proposed spending cuts before they take effect. However, Trump announced the latest reductions with only five days remaining in the federal fiscal year, leaving lawmakers little time to intervene.

The Government Accountability Office has said the tactic, known as a “pocket rescission,” is illegal.

Collins described the move as the latest attempt by OMB to “undermine Congress’s Constitutional power of the purse.”

Trump used the same approach a year ago for the first time in five decades, blocking $4.9 billion in foreign aid approved by Congress. The US Supreme Court declined to block those cuts, citing the administration's authority over foreign affairs as a significant factor in its decision.

This time, the administration is targeting domestic spending.

The latest move comes amid a broader effort by the Trump administration to expand presidential control over the federal government, raising concerns about the erosion of congressional authority.

The administration has also dismissed federal employees, imposed a historic increase in tariffs and launched the war in Iran without seeking congressional approval, leaving the judiciary to determine the limits of presidential power.

Senator Patty Murray, the top Democrat on the Senate Appropriations Committee, condemned the funding cuts as “theft from the American people, plain and simple.”

“These are funds Congress has delivered on a bipartisan basis and should be helping people—not cut off by a president more focused on building a ballroom than investing in families,” Murray said.

Beyond immigrant services, the White House said the rescissions included $70 million for what it described as “woke” international education programmes, $28 million in grants for Health and Human Services research and $9 million in debt relief for foreign countries that fund climate change policies.

The administration was also withholding another $10 million from a minority business development programme.