Sources close to Capitol Hill and within the foreign aid community say that Trump administration officials are preparing a potential foreign aid “rescission” package that could cut between $2 billion and $4 billion in fiscal 2017 and fiscal 2018 funds from the State Department and U.S. Agency for International Development.

Some $200 million intended to benefit Palestinians in the West Bank and Gaza Strip is thought to be on the chopping block as part of the request, sources said.

The package is thought likely to be submitted in the final week of August, which would give Congress little chance of blocking it before a new fiscal year begins on October 1.

The 1974 Impoundment Control Act — intended to limit a president’s power to rescind already appropriated funds — requires Congress to approve such a request but gives lawmakers only 45 days to do so. During that period, the money targeted for rescission is frozen and cannot be obligated. If a request from Trump comes in the next couple of weeks, the administration may have unilateral authority to effectively cancel the funding, since it would expire once the current fiscal year ends, even if Congress doesn’t act.

Senate Foreign Relations Chairman Bob Corker at a hearing on Thursday said he doubted it would be legal for the administration to submit a rescission package inside the 45-day window but his office would look for ways to “counter that if that’s the case.”

“For them to counter what Congress has appropriated and do so in a manner that doesn’t give us time to react would obviously be a breach of trust,” the Tennessee Republican told reporters after the hearing.

The committee’s top Democrat, Robert Menendez of New Jersey, who appraised Corker of the situation, also said he was troubled.

“I hear that the administration is sending a rescissions package, which potentially would be a devastating blow to the State Department and USAID,” Menendez said. “And if it does so, and does so in a time frame in which Congress under the law cannot act — which I think would be illegal to do — that will have consequences.”

Menendez called on Secretary of State Mike Pompeo to “prevail upon the administration not to make such devastating blows.”

It’s understood among the foreign aid community that the withdrawn funding would come in part from Economic Support Fund and Development Assistance accounts, and that Office of Management and Budget Director Mick Mulvaney is leading the development of the rescission package.

“We do not comment on alleged leaks and will not discuss deliberative and pre-decisional information,” said an administration official, who declined to be named.

While few individuals familiar with Trump administration’s plans wanted to go on the record until the administration actually submits something concrete, foreign aid advocates are already strategizing to protect the funding.

One possibility raised was to include language in a continuing resolution that Congress will likely have to pass to keep the government funded beyond October 1. Such language could extend the expiring authorities for the appropriated foreign aid funds. That would require the consent of Senate Majority Leader Mitch McConnell, R-Ky., and House Speaker Paul D. Ryan, R-Wis. But it’s still seen as more likely than lawmakers mounting a legal objection under the Impoundment Act, given Republicans’ reluctance to directly challenge Trump.

A new rescissions request, if submitted, would be the second attempt by the Trump administration this year to cut spending previously blessed by Congress. In May, the president submitted a roughly $15 billion list of proposed cuts, with nearly half coming out of the Children’s Health Insurance Program; the House narrowly passed the measure (HR 3) in June but it was blocked in the Senate on a 48-50 vote. 

Some Democrats thought there would be sufficient bipartisan support to block another attempt to get around lawmakers’ constitutional power of the purse, particularly on foreign assistance funds.

“The president from the proposal of his budget to the current moment continues to make efforts to defund or significantly undermine the work of our State Department and USAID,” Senate Foreign Relations member Chris Coons, D-Del., told CQ Roll Call. “Fortunately, on a bipartisan basis, we’ve consistently rejected those cuts. I view this rescission strategy as just another way to make harmful cuts to our work around the world.”

Kellie Mejdrich contributed to this report.

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