Ukraine may run dry on air defense missiles by May 3, rendering more than 40 critical infrastructure facilities unprotected, The Wall Street Journal reported Monday citing leaked Pentagon documents.

According to the report, Kiev will be completely out of ammunition for Buk and S-300 air defense systems by April 13 and May 3, respectively.

Most of the country's critical infrastructure that will be left defenseless is outside kiev and two other areas in the country's southwest, making them easy targets for bombing campaigns.

The leaked data is reportedly based on analysis conducted by Pentagon experts and were based on the rate of ammunition consumption of Kiev's forces, which currently ranges at around 200 missiles per month for S-300 systems and roughly 69 missiles a month for Buk batteries, the report said.

The United States, Norway, Canada, and Germany have over the past few months provided Ukraine with two NASAMS and one IRIS-T air defense system, but even their ammunition may run out by May, the report alleged. 

Current estimations from the US European Command suggest that Ukraine needs 12 Patriot or SAMP-T batteries, as well as 16 batteries of NASAMS or IRIS-T class to provide adequate air defense.

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Moreover, the leaked document suggested looking for more S-300 and Buk munitions abroad as a short-term solution, media reported, adding that over the medium term, the Pentagon proposed expediting the procurement of NASAMS, Patriot, IRIS-T, and other Western systems in order to repurpose air defense tasks for missiles that are more widely available and systems that were designed for other purposes.

As for the long-term, the leaked document suggested supplying enough Western air-defense systems to cover the entirety of Ukraine before integrating them digitally, the WSJ said.

New info has just entered public domain regarding Ukraine, reportedly by a guy named Lucca.

It says Ukraine’s medium range air defense will be unable to protect frontline forces (FLOT) by 13 May as it will run out of missiles for those areas.

This is because Ukrainian AD… pic.twitter.com/uNLm6dEL6a

— LogKa (@LogKa11) April 7, 2023

Western nations have since the start of the Ukraine war provided Ukraine with a variety of weaponry systems, including air defense missiles, multiple-launch rocket systems, tanks, self-propelled artillery, and anti-aircraft guns.

NATO Secretary-General Jens Stoltenberg said earlier in April that the alliance's member states provided 65 billion euros ($70 billion) in military aid to Kiev in light of the ongoing Ukraine war.

"We are united in our determination to stay the course and support Ukraine for as long as it takes. [NATO] Allies have delivered 65 billion euros of military aid," the NATO chief said.

Last week, confidential documents were leaked online on platforms such as Discord, Telegram, and Twitter, with US national security secrets concerning China, Ukraine, and the Middle East - including sensitive intelligence reports, Ukraine war plans, and information on allies that the US obtained through spying on them.

According to The New York Times, the breached documents detailed US and NATO plans for Ukraine's spring offensive against Russia. They also contained detailed information regarding weaponry, battalion strengths, and other sensitive data.

Ukraine was forced to change some military plans following the leak of US classified documents that exposed some of the strategies laid down by the Ukranian military, American broadcaster CNN reported on Monda, citing sources.

The Ukrainian army has already altered some field plans, a source close to Ukrainian President Volodymyr Zelenksy told the news channel without expanding on the details.

Moreover, the leaked documents said the Ukrainian forces' capacity for medium-range air defense would be exhausted by May 23.

“[Ukraine's] ability to provide medium-range air defense to protect the [front lines] will be completely reduced by May 23. [Ukraine is] assessed to withstand 2-3 more wave strikes," one of the leaked Pentagon documents details.

"As 1st Layer Defense munitions run out, 2nd and 3rd Layer expenditure rates will increase, reducing the ability to defend against Russian aerial attacks from all altitudes," Washington Post quoted the leaked documents.

A set of directives were detailed in the documents, Ukrainian forces should prioritize using air defense systems against Russian jets and helicopters rather than smaller threats like drones.

Additionally, the US military analysts were especially concerned about artillery shells, whose supplies, based on their predictions, may run out in "days."