Swedish soldiers take part in a military presentation of the medium-range Patriot air defense missile system in Stockholm, Sweden, April 30, 2023 (AP)

The US-made Patriot air defense systems and the Ukrainian forces the United States trained on the system arrived in Ukraine last week after completing training in the state of Oklahoma, Politico reported on Wednesday.

The Patriot systems and Ukrainian forces completed training at Fort Sill, Oklahoma, and were then transported to Ukraine, the report said, citing a senior US Defense Department official.

The Wall Street Journal reported in early April that Ukraine may run dry on air defense missiles by May 3, rendering more than 40 critical infrastructure facilities unprotected. The newspaper cited leaked Pentagon documents.

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

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.

Some 65 Ukrainian soldiers were undergoing training on how to operate the Patriot system at the Fort Sill base in Oklahoma, the United States. They are expected to continue preparations for operating the system in Europe once they finish training in the United States.

The soldiers, as reported by the Chairman of the Chiefs of Staff General Mark Milley, recently completed their training on the Patriot air defense system.

"In addition, there are about 2,500 Ukrainian soldiers conducting training right now in Germany. Another 8,800, almost 9,000, have completed training and returned to Ukraine," Milley said.

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.

That came after 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.

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 at the time.

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

Additionally, White House Press Secretary Karine Jean-Pierre revealed earlier on Wednesday that the US intended to send a new security aid package for Ukraine, set to include HIMARS ammunition and additional howitzers.

According to Secretary of State Antony Blinken, the United States has authorized $300 million in additional security support for Ukraine, including heavy artillery and ammunition, anti-tank weaponry, and other field equipment.

The announcement comes a day after Politico reported that the Biden administration is predicted to announce a fresh military aid package for Ukraine amounting to $300 million.