Iraqi Information Minister Mohammed Said al-Sahhaf denied claims by US commanders and reports from AFP journalists on the ground with US troops that American forces were now on the outskirts of Baghdad and very close to the city's airport.

He told a press conference here that US troops were "not even 100 miles" from Baghdad, but said Thursday's air strikes in and around the city had killed 27 civilians and wounded 193.

Baghdad's Saddam International Airport was Thursday afternoon, however, still under the full control of the Iraqi authorities, according to an AFP correspondent at the scene.

No bombing or fighting was visible at the airport, which lies 20 kilometres (12 miles) southwest of the centre of Baghdad.

"The airport is safe," airport manager Muafiq Abdullah al-Jaburi told journalists escorted there by the information ministry.

"Maybe the Americans occupied another airport in the desert," joked Jaburi.

Major Randi Steffy, a spokeswoman for the US Central Command in Qatar, earlier said that US forces were "outside the airport."

In Baghdad, a statement attributed to President Saddam Hussein and read on state television said Iraqi forces would never let the capital be taken.

"Many thousands of soldiers are defending the homeland ... and they will not allow them to go into Baghdad without defeating and repelling them," the statement vowed.

It said barely a third of Iraq's forces had yet been engaged in battle.

But US officers said 500 Iraqi troops were killed in clashes with US forces for a key bridge some 30 kilometres (20 miles) southwest of the capital, while other US soldiers were just half that distance from downtown Baghdad.

Major General Buford Blount, commander of the 20,000-strong US infantry division at the city's edge, said the US military now controlled the southern approaches to the capital.

Iraq has repeatedly warned that the war's decisive battle will be in Baghdad, where it could engage US-led forces in bloody street-to-street fighting. It also says it has thousands of volunteers ready to become "martyrs" in suicide strikes.

AFP reporters in Baghdad since the war began said the bombardment of the city has been more intense in recent days and that on Thursday afternoon it was unusually heavy. Massive explosions boomed from the southern outskirts.

Saddam's elite Republican Guard forces are said to be outside the city to the south, defending the capital from US and British troops that have been sweeping northward since entering Iraq from neighbouring Kuwait.

Iraq has denied US claims that two Guard divisions have been devastated by the air assault, which US commanders say has been intended to weaken the dug-in units of the 60,000-strong Guard.

More and more trenches filled with oil have been set ablaze around the city in an effort to hamper the visibility of coalition pilots, giving off thick black clouds and rendering the air noxious.

US and British warplanes launched at least two attacks on Baghdad's Republican Palace on Thursday, the third straight day the sprawling complex on the Tigris river was bombed.

US Central Command said coalition forces targeted the presidential bunker and residence along with the New Presidential Palace in the Al-Khark sector west of the Tigris.

Warplanes also struck a farm used as a command and control post southwest of Baghdad and a military store in the Iraqi capital, Centcom said.

Massive, booming explosions could be heard from the centre of Baghdad, and as night fell there was a heavy bombardment of the western outskirts around 5:30 pm (1430 GMT) which continued for more than seven minutes.

The US and British bombing has racked up mounting civilian casualty tolls.

In the latest incident, eight civilians died and five were wounded Thursday by a missile that hit a vegetable market at Nahrawan on the southeastern edge of Baghdad, an Iraqi hospital source said.

US Central Command said it was investigating the incident, saying it had no information on it.

The wives and children of two close aides to Saddam Hussein's elder son Uday were killed in a US-British air strike on a farm north of Baghdad, relatives said.

Acyl Tabra, first vice-president of the Iraqi National Olympic Committee chaired by Uday, and Bashar Hisham, another member of the board, were not at the farm at the time of the bombings, the relatives said.

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