Biden promises Ukraine advanced air defense systems after Russian strikes

• "He also underscored his ongoing engagement with allies and partners to continue imposing costs on Russia, holding Russia accountable for its war crimes and atrocities, and providing Ukraine with security, economic, and humanitarian assistance," the statement added.

Between the lines: The White House did not detail which air defense systems Biden discussed with Zelensky during their call, but CNN notes the U.S. has already committed to providing Ukraine with national advanced surface-to-air missile systems, which could tackle Russian cruise missiles.

What they're saying: Zelensky told Biden during their phone conversation that Monday's missile strikes across Ukraine represented "pure terror," but were "a sign of weakness of the Russian army, which is losing on the battlefield," per a statement from the Ukrainian president's office.

• Along with discussing "the importance of air defense and continued U.S. contributions to increase this capability," they spoke about Tuesday's planned call with Zelensky and the G7 leaders on supporting Ukraine, according to the Ukrainian president's office.

The big picture: The Biden administration last month announced the U.S. would provide Ukraine with $600 million in military aid, in addition to an August package totaling nearly $3 billion, plus previous assistance worth $550 million, $1 billion and $775 million.

Editor's note: This article has been updated with comment from the Ukrainian president's office.