Comment U.S. monitors have conducted in-person inspections of only about 10 percent of the 22,000 U.S.-supplied weapons sent to Ukraine that require special oversight. US officials, who spoke on condition of anonymity to provide previously undisclosed details, said they were scrambling to develop new means to track weapons deemed to have an increased risk of diversion, including Stinger surface-to-air missiles and anti-tank missiles. Javelin, in the midst of what they describe as Ukraine’s “super hot conflict.” They hope to achieve a “reasonable” level of compliance with US oversight rules for these high-risk species, but also acknowledge they are unlikely to achieve 100 percent of normal controls and stockpiles as the country’s escalating war with Russia strains systems to ensure weapons are not stolen or misused. Since late February, which led to the closure of the US Embassy in Kyiv for several months, US officials have been able to conduct only two in-person inspections of items requiring enhanced surveillance at weapons depots where US weapons had been transferred from Poland. “The conflict creates an imperfect environment for us to adapt quickly,” said a senior State Department official. “We want to allocate some of those resources to work with our allies and partners to mitigate risk, however, where we can.” The struggle to adjust oversight rules designed for peacetime has taken on greater importance as the volume of US aid skyrockets and congressional scrutiny intensifies. U.S. and Ukrainian officials say they have documented no cases of the illegal use or transfer of U.S. weapons into Ukraine since Russian President Vladimir Putin launched his invasion on February 24. The State Department has acknowledged that the seizure of Ukrainian weapons by Russian forces could lead to those weapons being smuggled into other countries. Other weapons have been lost. a Swedish grenade launcher, apparently stolen from a battlefield in Ukraine, exploded in the trunk of a car in Russia in May. Arms trade experts warn the government and its allies must remain wary despite widespread Western support for Kiev’s push to counter Putin’s invasion and the brutal tactics his forces have used against Ukrainian cities and civilians. . Rachel Stohl, vice president for research programs at the Washington-based Stimson Center, said officials also need to develop long-term plans to ensure the safety of surplus U.S. weapons once the conflict with Russia ends, noting Ukraine’s history as a theater for small arms smuggling after the Cold War. He said calls for close supervision may seem at odds with the United States’ desire to help at a moment of existential importance in Ukraine. But he added: “We need to make sure we don’t let the pace and urgency outweigh our long-term interests.” The challenges in Ukraine echo larger concerns about how weapons produced in the United States, the world’s largest arms seller, are used worldwide. Advocates have long complained that despite systems designed to prevent their misuse, foreign partners have sometimes used these weapons against civilians in places including Yemen. Sophisticated equipment has also fallen into the hands of opponents, allowing the Islamic State to field Abrams tanks and the Taliban to pilot Black Hawk helicopters. The Biden administration is trying to signal a new oversight push to account for any potential leakage from the large flow of American weapons — especially as congressional Republicans express growing concerns about aid accountability and the overall volume of aid to Ukraine. Passing massive aid packages could become more difficult after next week’s midterm elections. Last week, the government unveiled a plan to prevent the diversion of arms to Eastern Europe. For almost $18 billion in US military aid provided since February alone, the Biden administration’s aid to Ukraine is the largest such amount since the end of the Cold War. National Security Council spokeswoman Adrienne Watson said Kyiv has been a “willing and capable” partner in weapons accountability. “While we recognize the unpredictability of combat, the United States and Ukraine have worked together to prevent the illicit diversion of weapons since Russia’s further incursion began earlier this year,” he said. U.S. officials say Ukraine is working hard to show its compliance with weapons accountability requirements from the United States and other countries, in part because local officials know any documented cases of diversion could weaken strong Western support that is vital to their struggle. Most of the equipment supplied to Ukraine to date is subject to only minimal tracking requirements under the US arms control system, known as “end-use tracking”. For items such as small arms ammunition or personal protective equipment, considered to pose a lower proliferation risk, a US military officer in eastern Poland is assigned the sole task of overseeing the transfer of control of this equipment from US hands to Ukrainian hands; including a process in which officials from both countries record the species. As with any other transfer of US military equipment, Ukraine must commit not to transfer the weapons to other nations without US permission. But it exists little routine monitoring afterward, officials said. More sophisticated or sensitive equipment requires an additional set of checks, including an annual inspection, conducted — under normal circumstances — by a U.S. officer to ensure the weapons are stored safely and serial numbers match. These items also include Switchblade drones and night vision devices. These devices make up about half of the items subject to additional monitoring. Larger weapons systems, such as HIMARS multiple launch missiles and the M777 howitzer, do not require enhanced tracking. Officials acknowledged that when the war broke out, they had no plan for tracking weapons in a conventional conflict like the battle in Ukraine. US personnel are unable to venture into the vast swaths of the country occupied by Russian forces or facing active combat. To offset these limitations, officials are relying on technology first embraced during the coronavirus pandemic, using scanners that would allow Ukrainian personnel to capture serial numbers without US personnel present. The inventory information — which is recorded without geo-locating the items, for operational security purposes — is then uploaded and provided to US officials. American personnel have begun training Ukrainian peers in Poland on the new scanner technology. Officials are trying to develop this countermeasure ahead of the war’s first anniversary in February, after which many weapons will potentially fall out of compliance. The challenges are compounded by the size of the growing, but still small, security cooperation group. U.S. officials are also trying to account for weapons used by Ukrainian forces by scanning canisters of spent weapons and receiving spending reports from the Ukrainian military. Ukraine has also provided “a handful” of reports of losses when equipment, mainly night vision equipment, is damaged, they said. While damage and expense reports are still received in paper form, officials hope that this too will soon be automated, making it easier to get a real-time picture of how US weapons are being used against Russia. A 2020 report by the Pentagon’s inspector general found that defense officials had complied with tracking requirements for Javelins and their launchers supplied to Ukraine, but had not fully complied with night vision devices. He cited the Ukrainian military’s failure to consistently report the loss or theft of these items and found that serial numbers were sometimes dropped or made illegible, preventing proper stockpiling. In Kyiv, officials say the nature of the fighting — in which Russian forces regularly strike Ukrainian cities and torture Ukrainian civilians — makes diversion of weapons unthinkable. Oleksandr Zavytnevych, who heads Ukraine’s parliament’s defense and national security committee, said members of a parliamentary committee set up this year to monitor weapons had visited weapons caches and looked into rumors of diversion or theft, but found no “real signs” of illegal activities . U.S. officials say Ukraine’s military is now trying to update its own system to digitally track donated weapons, just as the military does for maintenance and logistics. The Biden administration has begun informing other nations that supply Ukraine about the US surveillance process in Ukraine. So far, while there are new mechanisms for loosely coordinating arms donations, there is no central international tracking system. US officials acknowledge they are unlikely to be satisfied with the overall results of the evolving oversight approach – which they hope will achieve “greater than zero” assurances for US taxpayers – but say that should not be seen as a reason for restraint American support. “It is our moral and ethical responsibility to help the people in the government of Ukraine, and the consequences of not doing that are much worse,” the State Department official said. “So in terms of cost-benefit, this seems very clear.” Serhiy Morgunov in Kyiv, Ukraine, and Dan Lamothe and Alex Horton in Washington, D.C. contributed to this report.