President Donald Trump's administration asked the Supreme Court on Monday to intervene in its bid to withhold billions of dollars in foreign aid authorised by Congress, part of the Republican leader's effort to scale back US assistance abroad.
The Justice Department asked the court to halt Washington-based US District Judge Amir Ali's order requiring officials to take steps to spend the $4 billion they have sought to claw back.
Congress had intended for that sum to be spent on foreign aid, UN peacekeeping operations and promoting democracy overseas.
The Justice Department said the administration views the proposed withholding of $4 billion overseas aid funding as "contrary to US foreign policy".
Congress budgeted billions in foreign aid last year, about $11 billion of which must be spent or obligated ahead of a deadline of September 30 – the last day of the US government's current fiscal year – lest it expire. After being sued by aid groups that had expected to compete for the funding, the administration said last month it intended to spend $6.5 billion of the disputed money.
Mr Trump also sought to block $4 billion of the total through an unusual step called a "pocket rescission" that bypasses Congress.
Mr Ali ruled on September 3 that the administration cannot simply choose to withhold the money and that it must comply with appropriations laws unless Congress changes them.
The judge's injunction "raises a grave and urgent threat to the separation of powers", Justice Department lawyers wrote in Monday's filing. It would be "self-defeating and senseless for the executive branch to obligate the very funds that it is asking Congress to rescind", they added.
Under the US Constitution, the government's executive, legislative and judicial branches are assigned different powers.
Mr Trump's budget director Russell Vought has argued that the President can withhold funds for 45 days after requesting a rescission, which would run down the clock until the end of the fiscal year. The White House said the tactic was last used in 1977.
Lauren Bateman, a lawyer for a group of plaintiffs, said on Monday the administration is asking the Supreme Court "to defend the illegal tactic of a 'pocket rescission'".
"The administration is effectively asking the Supreme Court to bless its attempt to unlawfully accumulate power," Ms Bateman said. In a 2-1 vote on Friday the US Court of Appeals for the District of Columbia Circuit declined to halt Mr Ali's order, prompting the administration's request to the Supreme Court.
The administration has repeatedly asked the justices this year to intervene to allow implementation of Trump policies impeded by lower courts. The Supreme Court, which has a 6-3 conservative majority, has sided with the administration in almost every case which it has been called upon to review since Mr Trump returned to the presidency in January.
Earlier in the foreign aid funding case, the court in March voted 5-4 to decline to permit the administration withhold payment of about $2 billion to aid organisations for work they had already carried out for the government.