The United States has confirmed that Ukraine has begun using long-range ballistic missiles provided covertly by the US against Russian forces. These missiles, part of a $300 million aid package authorized by President Joe Biden in March, were delivered this month and have already been employed to strike Russian targets in occupied Crimea, according to US officials.

President Biden has now signed off on an additional $61 billion aid package for Ukraine. Previously, the US had supplied Ukraine with a mid-range version of the Army Tactical Missile Systems (ATACMS) but had been hesitant to send more potent weaponry due to concerns about compromising US military readiness. However, Biden reportedly approved sending the longer-range ATACMS in February.

The decision to provide these missiles was kept quiet initially to maintain operational security for Ukraine, as requested by Ukrainian officials. The exact number of missiles sent is unclear, but the US plans to send more, according to National Security Advisor Jake Sullivan.

The deployment of these longer-range missiles was first acknowledged when they were used to strike a Russian airfield in occupied Crimea last week, as reported by Reuters. They were also reportedly used in an attack on Russian troops in the occupied city of Berdyansk.

Ukraine has intensified its appeals for Western assistance as its ammunition stocks dwindle and Russia advances steadily. President Zelensky welcomed the new aid package, emphasizing the urgency to counter Russian plans.

Recent setbacks, like the loss of Avdiivka during the winter, have prompted concerns about a potential Russian offensive in the coming weeks. Ukrainian forces have faced challenges due to ammunition and air defense system shortages, which officials attribute in part to delays in military aid from the US and other Western allies.

Since Russia’s invasion of Ukraine on February 24, 2022, tens of thousands of people, mostly soldiers, have been killed or injured, and millions have been displaced.