President Donald J. Trump participates in a bilateral meeting with Australian Prime Minister Scott Morrison Friday, Sept. 20, 2019, to the Oval Office of the White House.

As Congress races against a looming October 1 deadline to avert a government shutdown, Sen. Lisa Murkowski (R-Alaska) sharply rebuked the Trump administration’s attempt to unilaterally retract nearly $5 billion in foreign aid.

In a post on the social platform X Tuesday, Murkowski criticized what she called “the Office of Management and Budget’s unlawful attempt to pursue a nearly $5 billion pocket rescission.”

The Alaska Republican, who often breaks with President Donald Trump on policy issues, stressed that “Congress alone bears the constitutional responsibility for funding our government, and any effort to claw back resources outside of the appropriations process undermines that responsibility.”

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Murkowski, a member of the Senate Appropriations Committee, warned that the move would “only threaten the good bipartisan work that has been done in committee and on the floor, and risk throwing the entire process into chaos.”

On Friday, Trump shook up September’s government funding talks on Capitol Hill by asserting the authority to cancel billions in foreign aid using a so-called pocket rescission.

The White House budget office announced Friday that Trump has canceled $4.9 billion using this tactic. Congress’ top watchdog and many lawmakers are calling this move an illegal bypass of their “power of the purse.”

Sen. Susan Collins (R-Maine) slammed the action as "a clear violation of the law," in a statement issued Friday. She emphasized that “the Constitution makes clear that Congress has the responsibility for the power of the purse.”

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Senate Minority Leader Chuck Schumer (D-N.Y.) denounced it as an “unlawful gambit to circumvent Congress,” warning it threatens a “painful and entirely unnecessary shutdown.”