Iraqi troops failed to recapture jihadist-held areas of Anbar provincial capital Ramadi in a night-time assault that left four civilians dead, medical and security officials said on Tuesday Al Arabia reported.
Fighters loyal to the Islamic State of Iraq and the Levant (ISIL) were still in control of the south of the city, west of Baghdad, after fighting off the assault, police said.
"Security forces and armed tribesmen tried last night to enter areas controlled by the ISIL in the south of the city," a police captain in Ramadi told AFP.
"Clashes erupted at 11 pm (2000 GMT) and ended this morning at 6 am (0300 GMT). The security forces failed to enter these areas and ISIL is still in control."
Four civilians were killed and 14 wounded in the fighting, Dr Ahmed Abdel Salam of Ramadi hospital told AFP.
Due to concerns regarding more civilian casualties, Staff Lieutenant General Mohammad al-Askari told AFP, "It is not possible to assault it (Fallujah) now."
He had no figures for any casualties in the ranks of either the army or the jihadists.
ISIL loyalists took advantage of a surge of anger among Sunni Arabs at the clearance of a year-old protest camp outside Ramadi on Dec. 30 to seize large swathes of the city and the whole of Fallujah to its east.
Three loud explosions were heard outside Fallujah early Tuesday, a witness said.
The army was continuing to hold positions outside the city to allow civilians time to leave before launching an assault, security sources said.
"Today the army deployed new reinforcements backed by tanks and armored vehicles to an area about 15 kilometers (10 miles) east of Fallujah," a police captain told AFP.
Prime Minister Nouri al-Maliki has ordered the army to prepare an offensive to regain control of both Fallujah and Ramadi.
But he has said he wants to give Anbar province's heavily armed tribes time to expel ISIL fighters before going ahead.