The U.S. Embassy in Kyiv, along with several other Western embassies, closed due to a warning of a potentially significant Russian air attack, marking an unusual level of specificity in threat details. This closure follows Ukraine's use of U.S.-made ATACMS missiles to strike Russian territory, which heightened tensions with Russia, leading to a change in their nuclear doctrine allowing potential nuclear retaliation against non-nuclear states backed by nuclear powers. Despite the closures, Ukraine downplayed the threat, labeling it as part of routine Russian air attacks and accused Russia of spreading misinformation about large-scale strikes. Meanwhile, the UK Embassy in Kyiv remained open with limited operations, emphasizing the ongoing daily realities of the conflict. Western leaders view Russia's nuclear posture change as an intimidation tactic, while the U.S. has also authorized new military aid to Ukraine, including antipersonnel landmines.