In a telephone call Monday, Blinken welcomed Prime Minister Mohamed Shia al-Sudani's condemnation of the attacks on bases where US troops are stationed as part of an international coalition to fight the Islamic State group.

Blinken "urged the prime minister to pursue those behind the attacks and fulfill Iraq's commitment to maintain the security at these installations," State Department spokesman Matthew Miller said.

Most of the attacks have been claimed by a group called "Islamic Resistance in Iraq" on Telegram channels affiliated with Shiite factions loyal to Iran, the sworn enemy of Israel.

National Security Council spokesman John Kirby said Monday that Iran in some cases was "actively facilitating" attacks against US forces.