Shiite militias today converged on Ramadi to try to recapture it from jihadists who dealt the Iraqi government a stinging blow by overrunning the city in a deadly three-day blitz.
The loss of the capital of Iraq's largest province was Baghdad's worst military setback since it started clawing back territory from the Islamic State (IS) group late last year.
Washington, which had made Anbar -- of which Ramadi is the capital -- a cornerstone of its assistance to Baghdad against IS, admitted to a "setback".
Prime Minister Haider al-Abadi had been reluctant to deploy Shiite militias to Anbar province for fear of alienating its overwhelmingly Sunni Arab population.
He favoured developing locally recruited forces, with support from the United States.
But militia commanders said Monday Ramadi's fall had shown the government could not do without the Popular Mobilisation units (Hashed al-Shaabi).
Badr militia chief Hadi al-Ameri, a senior figure in the Hashed who has been critical of the government's policies in Anbar, went to Habbaniyah, near Ramadi, Monday to discuss operations.
With the huge numbers and battle experience of the paramilitary groups, a counter-offensive was expected to start soon, before IS has time to build up its defences.
Abadi "ordered the setting up of new defence lines in Ramadi, to reorganise and deploy the fighting troops to face" the jihadists, his office said after he met Iran's visiting defence minister, Hossein Dehghan.
Various militias announced they had units already in Anbar -- including around Fallujah and Habbaniyah -- ready to close in on Ramadi.
A spokesman for Ketaeb Hezbollah, a leading Shiite paramilitary group, said it had units ready to join the Ramadi front from three directions.
"Tomorrow, God willing, these reinforcements will continue towards Anbar and Ramadi and the start of operations to cleanse the areas recently captured by Daesh will be announced," Jaafar al-Husseini told AFP, using an Arabic acronym for IS.
Asaib Ahl al-Haq, a group routinely accused of abuses, said it had more than 3,000 fighters waiting for a green light.
