Sergey Supinsky | AFP | Getty Images WASHINGTON – The Biden administration announced a $1 billion security aid package for Ukraine on Monday, the largest arms tranche since Russia’s full-scale invasion began in late February. The upcoming military aid package, the 18th such tranche, brings the US commitment to about $9.8 billion and includes ammunition for long-range weapons and armored medical transport vehicles. The package consists of additional ammunition for High Mobility Artillery Missile Systems, or HIMARS, 75,000 rounds of 155mm ammunition, 20 120mm mortar systems and 20,000 rounds of 120mm mortar ammunition as well as ammunition for the National Advanced System-A Surface-to-Missir, or NASAMS. HIMARS, manufactured by defense giant Lockheed Martin, are designed to launch a variety of missiles from a mobile 5-tonne truck and have been high on Ukraine’s wish lists. Undersecretary of Defense for Policy Colin Kall said the US is not sending HIMARS in this latest package, only ammunition for the system. Kahl declined to say how many cartridges would be in the next delivery. The US has so far provided 16 HIMARS to Ukraine. The Pentagon will also send 1,000 Javelins, hundreds of AT4 anti-armor systems, 50 armored medical care vehicles, anti-personnel munitions, explosives, demolition munitions and demolition equipment. Until now, the largest aid package for Ukraine was announced on June 15, but this installment was a combination of the presidential withdrawal authority and the Ukraine Security Initiative. Monday’s package, solely a presidential withdrawal authority, means the weapons come directly from US stockpiles. “We will continue to consult closely with Ukraine and ramp up additional available systems and capabilities carefully calibrated to make a difference on the battlefield and strengthen Ukraine’s eventual position at the negotiating table,” said Secretary of State Anthony Blinken.