The US plans to announce as soon as this week that it has purchased an advanced, medium-to-long range surface-to-air missile defense system for Ukraine, a source familiar with the announcement tells CNN.

President Joe Biden, who is currently meeting with G7 leaders in Germany for a summit primarily focused on Ukraine, announced recently that the US would provide Ukraine with “more advanced rocket systems and munitions” as its war with Russia grinds on. Ukrainian President is slated to virtually address Biden and other G7 leaders.

In response to requests by Ukrainian forces, other military assistance is also likely to be announced this week, including additional artillery ammunition and counter-battery radars. Ukrainian officials have asked for the missile defense system, known as a NASAMS system, given the weapons can hit targets more than 100 miles away, though the Ukrainian forces will likely need to be trained on the systems, a source said.

The US has been steadily announcing additional security assistance for Ukraine. Last week, the Biden administration announced an additional USD 450 million in military assistance for Ukraine, giving it four more multiple launch rocket systems and artillery ammunition for other systems.