Ukrainian President Volodymyr Zelensky stands in front of a Patriot anti-aircraft missile system during his visit to a military training area in Germany, 11 June 2024. Photo: EPA-EFE/JENS BUETTNER / POOL

The United States has suspended the supply of Patriot missiles and other critical ammunition to Ukraine, Politico reported on Tuesday, citing sources, with White House Deputy Press Secretary Anna Kelly subsequently confirming the development to reporters.

The decision to suspend deliveries was made by the head of the Pentagon’s political department, Elbridge Colby, after a review of munitions stockpiles, sources told Politico, which led to “concerns” that its own stocks of artillery shells, anti-aircraft missiles and high-precision ammunition were decreasing.

A decision “was made to put America’s interests first” following a Department of Defence review of the US “military support and assistance to other countries across the globe,” Politico quoted Kelly as saying. “The strength of the United States Armed Forces remains unquestioned — just ask Iran,” she added.

The suspension will affect Patriot interceptors that can defend against incoming Russian missiles, Howitzer munitions, Hellfire missiles, precision-guided missile systems, Stinger surface-to-air missiles, AIM air-to-air missiles and grenade launchers, sources with knowledge of the decision told NBC News.

No comment has been made on how long the pause in deliveries might last.

The suspension comes as fighting between Moscow and Kyiv has intensified in recent months, with Russian airstrikes on Ukrainian cities showing no signs of abating.