The United States Pentagon announced on Tuesday that the U.S. will train Ukrainian personnel at a site in Oklahoma on how to operate and maintain the advanced Patriot air defense system that Washington is supplying to Kyiv.

"Training for Ukrainian forces on the Patriot air defense system will begin as soon as next week at Fort Sill, Oklahoma," Pentagon Press Secretary Brigadier General Pat Ryder said.

At the end of the previous year, Washington promised Ukraine a Patriot battery to help fend off Moscow's constant aerial assaults. This was a major triumph for Kyiv, which had pressed Washington for the system on numerous occasions.

"The training will prepare approximately 90 to 100 Ukrainian soldiers to operate, maintain and sustain the defensive system over a training course expected to last several months," Ryder said. "Once fielded, the Patriot will ... contribute to Ukraine's air defense capabilities and provide another capability to Ukrainian people to defend themselves against Russia's ongoing aerial assaults," he added.

By shielding Ukraine from attacks and preventing Moscow's forces from seizing control of the sky, air defenses have been instrumental in keeping the country safe. But when Russia suffered growing setbacks on the ground, it started deliberately attacking Ukraine's vital infrastructure. These attacks have cut out electricity, water, and heat to millions of people.

The MIM-104 Patriot is a surface-to-air missile (SAM) system produced by Raytheon that was intended designed to target high-flying aircraft. It was first employed in combat against Iraq's Russian-made Scud missiles during the first Gulf War, and it was updated in the 1980s to concentrate on the new danger of tactical ballistic missiles.

Patriot has proven successful in Saudi Arabia against ballistic missiles of Iranian design launched from Yemen, and its main contractor Raytheon claims the system has successfully intercepted more than 150 ballistic missiles since 2015.

Building multi-layer air defenses for Ukraine with low-, medium-, and high-altitude systems that can defend against a range of threats is the aim of the nation's international backers.

In retaliation, Russian President Vladimir Putin ridiculed the Patriot system as outdated and threatened to "knock down" its defenses with his forces. A surface-to-air system called Patriot missiles can take down swift aerial targets like cruise missiles.

Also on Tuesday, Justin Trudeau, the prime minister of Canada, declared that his nation would purchase for Ukraine a National Advanced Surface-to-Air Missile System (Nasams) developed in the United States. "This is the first Canadian donation of an air defense system to Ukraine," Canada's Defence Minister, Anita Anand, on Twitter said.