A source familiar with the matter told Reuters on Sunday that the United States is likely to announce the purchase of an advanced medium to long range surface-to-air missile defense system for Ukraine this week.
Washington is expected to announce other security assistance for Ukraine, including additional artillery ammunition and counter-battery radars to address needs expressed by the Ukrainian military, the source said.
Since Russia invaded its eastern European neighbor in February, Ukraine has been offered the weaponry from the United States.
President Joe Biden agreed to provide Ukraine with $700 million in military aid this month, including advanced rocket systems that can strike long-range targets with precision.
Ammunition, counter fire radars, a number of air surveillance radars, additional Javelin anti-tank missiles, as well as anti-armor weapons are also part of the package, officials said.
Another effort to sell four large, armable drones to Ukraine was stopped earlier this month because of concerns that their radar and surveillance equipment could create a security risk for the United States if it falls into Russian hands.