Lawmakers who are furious about President Trump’s decision to circumvent Congress and sell weapons to Saudi Arabia and other Gulf allies are now searching for a way to thwart the sale.

Experts say legislative options exist despite Trump’s move to invoke emergency powers that waive a congressional review period for the deals. But any attempt to block the president faces an uphill battle in a divided Congress.

Still, arms control advocates are hopeful the issue has ignited enough bipartisan outrage for lawmakers to take action.

“Congress blocking an arms sale like this would be pretty much unprecedented, but given that both the House and Senate approved Yemen War Power Resolutions, including with the support of Republicans in both the House and Senate, I believe the chance of a blocking action is high,” Jeff Abramson, a senior fellow at the Arms Control Association, said in an email.

Earlier this year Congress passed a war powers resolution to end U.S. military support for the Saudi-led coalition’s campaign in Yemen’s civil war. Trump vetoed the measure, and lawmakers fell short of the votes needed to override the veto.

Sen. Bob Menendez (N.J.), the top Democrat on the Senate Foreign Relations Committee, had legislative holds on arms sales to Saudi Arabia and the United Arab Emirates (UAE) over concerns about civilian casualties in the Yemen war, where the Saudi coalition has been blamed for the majority of civilian deaths.

Under normal procedures outlined in the Arms Export Control Act, lawmakers have 30 days to review and potentially block an arms sale once an administration formally notifies Congress about the pending action.

But on Friday, the Trump administration notified Congress it was invoking a provision of the law that allows sales to go through immediately without a review period in cases deemed an emergency.

The administration is using that emergency authority to push through 22 separate deals with the Saudis, Emiratis and Jordanians, with a total value of $8.1 billion. Notices for seven of the sales were posted on the Defense Security Cooperation Agency website Friday, while notices for the rest are expected to be published in the Federal Register.

The Friday notices show the sales include surveillance aircraft support and maintenance of aircraft for the Saudis, as well as 20,004 precision-guided munitions kits, 331 anti-tank missiles and 20 drones for the Emirates.

Lawmakers who oppose the move argue Trump is setting a dangerous precedent of invoking emergency authorities to avoid a vote in Congress, one they say he would not win.

Even Republicans who are generally supportive of Trump were dismayed at his decision to push the arms sales.

“I understand the administration’s frustration that key members of Congress held these arms sales for an extended period of time, in some cases for over a year,” Rep. Michael McCaul (R-Texas) said in a statement after Friday’s notification. “However, the president’s decision to use an emergency waiver on these sales is unfortunate and will damage certain future congressional interactions.” 

Despite the use of emergency powers, Congress could pass resolutions blocking the sales, Abramson said.

“At any point up until delivery, Congress could pass a joint resolution blocking a sale and should immediately consider doing so,” he said.

To help, he added, the chairmen and ranking members of the House Foreign Affairs and Senate Foreign Relations committees can request 30-day pre-delivery notifications.

“Congress still has many paths it can take to both register concern about the president misusing emergency powers in this instance and ultimately act to stop the sales and shipments,” he said. “This starts with speaking out, as many have already, making their displeasure clear.”

Several lawmakers have pledged to pursue legislation on the issue, but few have offered specifics.

Menendez in his statement said he was “in discussion with several Democratic and Republican colleagues,” adding that he hoped “the Senate Foreign Relations and the House Foreign Affairs Committees will soon be able to expeditiously address this latest attack on our constitutional responsibilities.”

Menendez’s office did not respond to a request for further details on Tuesday.

Sen. Chris Murphy (Conn.), the top Democrat on the Foreign Relations subpanel with oversight of Middle East affairs, similarly said in his statement he is “working on legislation to restrict arm sales.”

His office said Tuesday it did not have more specifics.

Menendez and Murphy are among the senators who previously offered a bipartisan bill that would suspend transfers of weapons to Saudi Arabia. The measure was first introduced in 2018 amid outrage over the Saudis’ killing of U.S.-based journalist Jamal Khashoggi. The legislation was introduced again in February.

Co-sponsors of the bill, known as the Saudi Arabia Accountability and Yemen Act, include Trump ally Sen. Lindsey Graham (R-S.C.), who has said he opposes the administration’s decision to use emergency authorities on the Saudi arms sales.

“I’ve got a real problem with going back to doing business as usual with Saudi Arabia,” Graham said on “Fox News Sunday.” “Jordan is a great ally. The UAE has been problematic in Yemen, but a good ally. Saudi Arabia is a strategic ally, but the crown prince was, in my opinion, involved in the murder of Mr. Khashoggi, and he’s done a lot of other disruptive things. So I don’t support the arms sales now.”

Senate Foreign Relations Committee Chairman Jim Risch (R-Idaho) has not committed to taking up the Saudi accountability bill.

Risch’s office did not respond to a request for comment Tuesday, and his Friday statement only said that he received the notification and is “reviewing and analyzing the legal justification for this action and the associated implications.”

The administration cited what it called a heightened threat from Iran as the reason for the emergency sales. The White House has pointed to the situation with Iran as the basis for deployments of more U.S. troops and weapons to the region.

The administration also noted that the emergency authority has been used at least four times before: in 1979, 1984, 1990 and 2006.

The 1984 example is “particularly relevant in this context,” a State Department official told The Hill on Tuesday. In that case, the Reagan administration cited “escalation” in the Iran-Iraq War, including attacks on Saudi oil tankers, and “ominous” trends in the war to expedite the sale of 400 Stinger missiles to the Saudis.

“In this determination, the U.S. government specifically pointed to the need to reassure partners of our commitment to their defense,” the official said. “Iran’s disruptive behavior has not changed in the 35 years since, and neither has the U.S. stalwart nature of our support for our Gulf partners.”

Lawmakers could also try to attach amendments to must-pass defense bills, like the National Defense Authorization Act (NDAA) and spending bills, coming through the House and Senate soon.

Sen. Chris Van Hollen (D-Md.) said in a statement after the notification he “will work to close this loophole in the appropriations process and use every available tool to prevent President Trump from taking this action.”

A Van Hollen staffer told The Hill on Tuesday that the senator is looking at ways to block Trump’s action in the annual appropriations bill for the State Department.

Rep. Ro Khanna (D-Calif.) also pledged to try to use the defense spending bill and NDAA to “stop bomb sales and end all forms of U.S. participation in this war” in Yemen.

Khanna, who was the chief House sponsor of the Yemen war powers resolution, told The Hill on Tuesday he is hopeful Trump’s decision on arms sales will give momentum to his effort to persuade House leadership to sue over Trump’s veto of the resolution.

“First it was the War Powers Resolution, now it’s arms sales,” he said in a statement to The Hill. “Once again, this president defied Congress to continue supporting the Saudis and Emiratis in their war in Yemen. I’m confident these new arms sales provides new momentum for pursuing legal action and legislation that would end U.S. involvement in the war.”