"The curfew will be lifted Monday at 6am, which includes the opening of the airport," said Bassem Ridha, advisor to Prime Minister Nuri al-Maliki.

But limited movement for official government and military vehicles will be permitted from Sunday, he said.

Heavy fighting continues

Earlier, US and Iraqi forces carried out a series of raids across the country and killed up to 50 insurgents. Rebels hit back, as a suicide bomber attacked a checkpoint in the western province of Al-Anbar, killing three civilians, including two children, and a US serviceman.

Meanwhile, Baghdad resounded to the sounds of mortar attacks in impromptu duels between rival Sunni and Shiite neighbourhoods that nonetheless caused few casualties.

Security officials also said fierce clashes took place in a number of areas of Baquba, the capital of Diyala, between security forces and insurgents. Up to 30 rebels were killed, though no further details were given.

Earlier in the day, the US military said its forces came under fire as they approached a suspected bomb-making facility near Taji, just north of Baghdad. In the ensuing gunbattle, 10 insurgents were killed.

Civilians caught in the crossfire

"During the exchange of fire, one pregnant woman and one teenaged male were injured," the statement said. The teenager later died of his wounds.

In another incident north of Baghdad, US forces killed 12 insurgents while en route to capture a militant "associated with the manufacturing of vehicle bombs and facilitating foreign fighters into northern Baghdad area," a separate statement said.

The success of security forces was overshadowed by reports that gunmen killed 21 Shiites, including a 12-year-old child, from the village of Imam Mansour in Diyala province.

Late on Friday gunmen raided two homes in the mostly Shiite village, dragged out 21 males and shot them execution style. Their bodies were found on Saturday.

In insurgent-plagued Al-Anbar, a suicide car bomber rammed a checkpoint and killed three Iraqis, including two children, and a US service member, the military said. The attack in Khalidiyah, a town between the strife-torn cities of Fallujah and Ramadi, also wounded nine civilians and another service member.

That death brings to 2871 the number of members of the military killed since the March 2003 invasion, according to an AFP count based on Pentagon figures.

Baghdad, the epicentre of the sectarian violence, remained under curfew for a second day on Saturday after the deaths of at least 300 people since Thursday, when the district of Sadr City was hit by the deadliest string of bombings against Shiites since the war began in 2003.

The airport was also closed, forcing President Jalal Talabani to postpone a trip to Tehran where he had been expected to discuss the country's security situation with his Iranian counterpart, Mahmoud Ahmadinejad. Talabani said he will travel when the airport reopens. His talks in Iran are expected to focus on engaging Baghdad's former foe in playing a greater role in helping curb the bloodshed in Iraq.

Cheney visits Saudi Arabia for talks

Meanwhile, heralding a new diplomatic thrust into the Middle East by Washington, Vice President Dick Cheney arrived in Riyadh on Saturday for talks with Saudi King Abdullah on regional issues, particularly Iraq.

Cheney may ask Abdullah to use his influence to help bridge the divide between Iraq's warring Sunni and Shiite factions, and also press for Riyadh to come through with promised reconstruction aid. His visit will pave the way for a meeting between President George W. Bush and Iraqi Prime Minister Nuri al-Maliki in Jordan on Wednesday.

Announcement of the meeting has triggered political turmoil in Baghdad, with the Iraqi leader's strong supporter, radical Shiite cleric Moqtada al-Sadr, threatening to withdraw from the national unity government if it goes ahead.

Sadr's people are accusing US troops of complicity, if not outright participation, in Thursday's Sadr City blasts. By far the largest attack in Iraq since the 2003 war in terms of fatalities, the bombings sparked new Shiite reprisals against Sunni Arabs. Alleged elements of Sadr's Mahdi Army attacked a number of mosques and Sunni homes in western Baghdad on Friday and killed around 30 people, security officials estimated.