WASHINGTON — The House on Friday passed 230-201 an additional $12.35 billion Ukraine aid package, including money to help Kyiv respond to a potential nuclear security incident, as part of its stopgap funding bill to avert a government shutdown.

The package includes $35 million in defense nuclear nonproliferation funding for the National Nuclear Security Administration to prepare Ukraine for a potential incident from shelling at the besieged Zaporizhzhia power plant. The Senate passed the government funding bill, complete with the Ukraine nuclear nonproliferation funding, 72-25 on Thursday and President Joe Biden is expected to sign it into law on Friday.

Craig Branson, a spokesman for the National Nuclear Security Administration, told Defense News in a statement the agency is “modeling potential consequences of damages to nuclear facilities” in Ukraine.

“Specifically, the funds will support procurement and maintenance of additional radiation sensors, data assessment and analysis, equipment and supplies for the National Guard of Ukraine for protective capabilities at nuclear facilities, counter-nuclear smuggling equipment for the Ukraine State Border Guard and potentially consolidation of radiological materials,” Branson wrote.

He noted the agency has already “provided significant assistance to Ukraine to monitor radiation levels” at sites such as Zaporizhzhia and the Chornobyl Exclusion Zone.

The Zapoprizhzhia power plant has come under frequent shelling in recent months amid Russia’s siege of the province. Russian shelling sparked a fire at part of the facility when Moscow first took control of the area in March.

International Atomic Energy Agency Director General Rafael Grossi led a delegation to inspect the plant earlier this month. After the visit, he called for a demilitarized protection zone around the power plant to avoid a potential nuclear incident if artillery hits the site.

Grossi said this week he is willing to start talks with Ukraine and Russia on setting up such a zone, but Russia has rejected previous calls for a demilitarized zone around the power plant.

“We are playing with fire and something very catastrophic could take place,” Grossi said after his visit.

The White House asked Congress for additional funding to bolster security around Zaporizhzhia before Russian President Vladimir Putin expanded his threats to use nuclear weapons in the conflict earlier this month.

Putin last week said he would use nuclear weapons if Russian territory comes under attack. During the same speech, he announced a referendum in Zaporizhzhia and other Russian-occupied areas of Ukraine. He proceeded to annex those areas on Friday.

“The risk of nuclear weapons use at this particular moment is higher than it has been in decades,” Daryl Kimball, the executive director of the Arms Control Association, told Defense News. “It is unprecedented in the post-Cold War era that a Russian or U.S. leader is threatening nuclear weapons use if their territory is at risk, but that’s what Vladimir Putin is doing.”

“We will have problems far beyond Ukraine, because the use of nuclear weapons could unfortunately quickly suck in NATO or U.S. military intervention, which then could lead to further escalation,” he added.

Biden declined to detail how the United States would respond should Russia use nuclear weapons in Ukraine during a 60 Minutes interview in September, but warned that doing so would “change the face of war unlike anything since World War II.”

Bryant Harris is the Congress reporter for Defense News. He has covered U.S. foreign policy, national security, international affairs and politics in Washington since 2014. He has also written for Foreign Policy, Al-Monitor, Al Jazeera English and IPS News.

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