Joe Biden's administration has deepened its involvement in the Ukrainian conflict by inviting up to 100 Ukrainian servicemen to the United States for training on the Patriot missile defense system, the Times writes.

U.S. Defense Department spokesman Brigadier General Patrick Ryder said the Ukrainians will travel to Fort Sill in Oklahoma as early as next week to begin a month-long training course to operate the Patriot battery, which can shoot down attack aircraft, cruise missiles and rockets.

Until now, Kyiv has only allowed its forces to leave the battlefield for short-term training with sophisticated weapons systems at European bases. But unlike other sophisticated systems sent to Ukraine, such as the High Mobility Artillery Missile System (HIMARS), the Patriots require intensive practical training outside Europe. Ukraine's decision to send its military overseas - for training that usually takes a year - underscores its armed forces' need for Patriots, as well as the Pentagon's long-term commitment to war.

The surface-to-air missile defense system consists of eight launchers, each with up to four truck-mounted interceptors along with a ground-based radar, control station and generator. About 100 soldiers are needed to operate one Patriot battery - about the same number are deployed to Fort Sill.

In December, the U.S. pledged to send a Patriot battery to Ukraine as part of a $1.85 billion military aid package.

The U.S. Army currently has 16 Patriot battalions and a training school located at Fort Sill.