The Pentagon’s decision to halt previously promised air defense systems to Ukraine was met with ominous warnings on Wednesday from Washington-based security experts, who warned the move will “encourage” and possibly “escalate” Russian President Vladimir Putin’s war ambitions.

The decision was confirmed by Fox News Tuesday night after Under Secretary of Defense for Policy Elbridge Colby assessed that the U.S. possessed dangerously low munitions stockpiles. 

However, experts are sounding the alarm that the move undermines U.S. and Ukrainian leverage as President Donald Trump looks to broker a ceasefire deal. 

A steelworker moves a 155 mm M795 artillery projectile during the manufacturing process at the Scranton Army Ammunition Plant in Scranton, Pennsylvania, on Thursday, April 13, 2023. (AP Photo/Matt Rourke)

In June, Russian forces broke their previous record for the number of drones fired at Ukraine in a single month by levying more than 5,300 drones in a series of mass attacks — up from the previous record set in March when nearly 4,200 drones were launched. 

“Putin has launched an intensified aerial assault, targeting civilians in cities across Ukraine with hundreds of drones and missiles,” founder and FDD President Clifford May told Fox News Digital. “Cutting off or even slowing munitions to Ukraine now can only encourage Putin to continue and even escalate this offensive. 

“That cannot be what President Trump wants,” he added.

Ukraine echoed these concerns on Wednesday and called the U.S. chief diplomat in Kyiv to meet with Foreign Ministry officials. 

“The Ukrainian side emphasized that any delay or slowing down in supporting Ukraine’s defense capabilities would only encourage the aggressor to continue war and terror, rather than seek peace,” the ministry said following its meeting with John Ginkel, deputy chief of mission at the U.S. Embassy in Kyiv.

Neither the U.S. Embassy nor the Ukrainian Foreign Ministry immediately responded to Fox News Digital’s questions regarding the meeting.

Overnight, Russia launched its largest aerial assault on Ukraine since the war started as fires burned in Kyiv on May 25, 2025. (Reuters/Gleb Garanich)

The attacks by Russia, which have increased in severity and frequency, have coincided with unsuccessful efforts to secure a ceasefire by the Trump administration, and come as Putin has also amassed some 50,000 troops along Ukraine’s northern border in what some fear could signal plans to launch another ground offensive. 

Special Envoy to Ukraine Gen. Keith Kellogg did not immediately respond to Fox News Digital’s questions over how the Pentagon’s order will impact the war and ceasefire attempts. 

Fox News’ Jennifer Griffen and Jasmine Baehr contributed to this report.