Herzog told reporters at the White House after his talks that they "mainly" discussed Iran's nuclear program, the crushing of protesters demonstrating against strict Iranian religious laws, and the issue of Tehran's drone sales to Russia.

The weapons are "killing innocent Ukrainian citizens," Herzog said. Israel has been reluctant to get involved in a US-led alliance helping pro-Western Ukraine to repel a bloody Russian invasion.

But Herzog's trip to Washington underlined Israeli concern at the growing role of Iran in the conflict, with Tehran accused of supplying fleets of deadly drones used by Russia against Ukrainian civilian targets.

On Tuesday, Herzog met with US Secretary of State Antony Blinken and announced he was sharing intelligence to prove that Iran has been supplying military drones to the Russians.

Ukrainian President Volodymyr Zelensky welcomed this Wednesday, saying "this is a positive trend in relations with Israel... After a long pause, I see us moving forward."

Biden and Herzog also discussed Iran's ongoing tussle with the international community over its nuclear program, which it insists have only civilian goals. Israel opposes a push by the Biden administration to salvage a deal that would reinstate international inspections in Iran in exchange for sanctions relief.

"They consulted on a wide range of global and regional issues of mutual concern, including the threats posed by Iran and its proxies. The president emphasized his administration's pledge to ensure Iran will never acquire a nuclear weapon," the White House said in a statement after the talks.