"Any (US) strike will result in an appropriate response," Al-Nujaba leader Akram al-Kaabi said in a statement, adding the group would continue its actions until its demands are met for US troops to leave Iraq and an end to Israel's war on Hamas in Gaza.

The Al-Nujaba movement forms part of the Islamic Resistance in Iraq, an alliance of Iran-backed armed groups that the United States has blamed for last weekend's deadly drone attack just over the border into neighbouring Jordan.

Another of the alliance's factions, Kataeb Hezbollah (the Hezbollah Brigades), announced earlier this week that it was suspending its attacks on US forces in Iraq and Syria, a decision that Al-Nujaba said it understood and respected.

But "the Islamic Resistance in Iraq, through its other factions, is going to fight on," it added.

The Al-Nujaba statement came as US President Joe Biden prepared to receive the bodies of the slain US soldiers at an air force base near Washington.

Biden has vowed a response to the deadly attack, the nature and timing of which have not been declared publicly.