FALLUJAH: A United Nations envoy has warned of a dire humanitarian situation in western Iraq, as Washington piled pressure on the Iraqi premier to quell an Al-Qaeda surge in the violence-plagued country.

More than 13,000 families have fled the militant-held city of Fallujah, the Iraqi Red Crescent said Wednesday, as masked gunmen held the city which is locked in a days-long standoff with the army.

And though traffic police returned to its streets, some shops reopened and more cars could be seen, Fallujah was still rocked by clashes and shelling, after an Al-Qaeda-linked group urged Sunnis to keep fighting the Shiite-led government.

Fallujah and parts of nearby Ramadi, both in the western province of Anbar, have been outside government hands for days -- the first time militants have exercised such open control in major cities since the insurgency that followed the 2003 US-led invasion.

The Iraqi Red Crescent said it had provided humanitarian assistance to more than 8,000 families across Anbar but that upwards of 13,000 had fled and were living with relatives, or in schools or other public buildings.

"There is a critical humanitarian situation in Anbar province which is likely to worsen as operations continue," Nickolay Mladenov, the UN special envoy to Iraq, said in a statement.

"The situation in Fallujah is particularly concerning as existing stocks of food, water and life-saving medicines begin to run out."

US Vice President Joe Biden called Nuri al-Maliki for the second time this week, mounting pressure on the Iraqi premier over the Al-Qaeda surge.

Biden urged Maliki to "continue the Iraqi government´s outreach to local, tribal, and national leaders," following the loss of Fallujah to Islamist insurgents, the White House said in a statement.

Spokesman Jay Carney said Washington was pressing Maliki to focus on political reconciliation as well as take military action to expel Al-Qaeda-inspired groups from Fallujah and Ramadi, both Sunni bastions in Anbar province, once liberated from extremists by US troops.

US Secretary of State John Kerry pressed home a similar message in a call with Iraqi Foreign Minister Hoshyar Zebari, the State Department said.

SOURCE: AFP