Monday witnessed warnings from the US that they would take action against those working with Iranian drones that Russia used in Kiev.

State Department Spokesperson Vedant Patel told reporters, "Anyone doing business with Iran that could have any link to UAVs or ballistic missile developments or the flow of arms from Iran to Russia should be very careful and do their due diligence -- the US will not hesitate to use sanctions or take actions against perpetrators," adding, "Russia deepening an alliance with Iran is something the whole world -- especially those in the region and across the world, frankly -- should be seeing as a profound threat."

Ukrainian officials claim 4 casualties as a result of the strikes, while Secretary of State Antony Blinken used the opportunity to validate supplying "everything possible" to Ukraine, as he told reporters at Stanford University in California, "It is a sign of increased desperation by Russia, but it's also a sign of the levels that they will stoop to and that we've seen repeatedly when it comes to targeting civilians and civilian infrastructure."

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Patel alleged in Washington that the UAV drones violated UN Security Council Resolution 2231, which bans Iranian exports of conventional weapons, claiming that Russia is being "forced" to turn to Iran and North Korea for supplies.

This comes at a time the flow of weapons into Ukraine is well underway, from European countries and the US. On October 15, US President Joe Biden ordered on Friday an additional $725 million in weapons shipments to Ukraine. The White House did not specify the nature of the latest disbursement, only that it would be another reduction in Defense Department "defense articles and services."

The US accuses Iran of supplying Russia with drones for use in the war in Ukraine, an accusation Tehran consistently denies. Just earlier this month, Iranian Foreign Minister Hussein Amir-Abdollahian strongly denied Iran's sale of drones and weapons to Russia for use in the war in Ukraine, stressing that the Islamic Republic of Iran "supports the political solution to the crisis in Ukraine." 

However, while US National Security Advisor Jake Sullivan accused Iran of selling unmanned drones to Russia which he argued would pose a threat if used in Ukraine, he stated on July 13 that the US has no evidence of such trade between the two nations.

"We have not seen evidence of delivery, but we have seen evidence of engagement between the two countries on this specific issue of large numbers of UAVs, including weapons-enabled UAVs for Russia to acquire from Iran," Sullivan said in his statement. 

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