United Nations and French forces prepared to attack Ivory Coast's presidential palace Tuesday after launching full assaults on the residence of the entrenched leader, the republican guard, two major military bases and state TV.

Fighters aiming to topple strongman Laurent Gbagbo had succeeded in taking nearly the entire countryside in just three days last week, but they faltered once they reached the country's largest city, where the presidential palace and residence are located.

With the help of international forces, the armed group fighting to install the country's democratically elected leader Alassane Ouattara pushed their way to the heart of the city to reach Gbagbo's home. They have surrounded it, and as of early Tuesday they were waiting for him to step down, said a close adviser to Ouattara who could not be named because he is not authorized to speak to the press.

Monday's offensive included air attacks on the ruler's home and on three strategic military garrisons and marked an unprecedented escalation in the international community's efforts to oust Gbagbo, who lost the presidential election in November yet has refused to cede power to Ouattara even as the world's largest cocoa producer teetered on the brink of all-out civil war.

A senior diplomat who could not be named because of the sensitivity of the matter said he had a map with blue stickers marking the six strategic points that needed to be taken out, and that five of the six had been hit by early Tuesday.

The five include Gbagbo's residence where heavy weaponry was destroyed, the republican guard, state TV, the Akban paramilitary base, and the arms depot at Akouedo which the diplomat said were bombarded by U.N. Mi-24 helicopters. A video posted on YouTube showed the depot being bombed. Tracers could be seen exploding from the burning core as Gbagbo's soldiers attempted to shoot down the helicopters.

"It's all over for Gbagbo — except the shooting," said the ambassador.

At Gbagbo's residence, the troops had created a perimeter around the building, waiting to see if he would come out or respond. Ouattara's adviser said that he had been told Gbagbo had created a bunker inside his residence, locked from within.

U.N. peacekeeping chief Alain Le Roy briefed the Security Council about the action in Ivory Coast on Monday and said international forces had targeted areas around the presidential palace where Gbagbo's forces were using heavy weaponry.

"There is no point to firing at the presidential palace if there are no heavy weapons," he said. "But we are seeing the heavy weapons very close and that is what we are firing on."

Postelection violence has left hundreds dead — most of them Ouattara supporters — and has forced up to 1 million people to flee. Ouattara has used his considerable international clout to financially and diplomatically suffocate Gbagbo and pro-Ouattara forces before launching a dramatic military assault last week.

On Monday, the U.N. fired on the Akouedo military base at around 5 p.m. local time (1700 GMT) to prevent Gbagbo's forces from using heavy weapons against civilians, said the spokesman for the U.N. Department of Peacekeeping Operations Nick Birnback.

Explosions resonated from the city's downtown core a few blocks from the presidential palace and near the base of the republican guard, and those living nearby barricaded their windows with mattresses. Flames could be seen licking the sky above the home of the staunchly pro-Gbagbo republican guard.

Just after the U.N. announced their attack, a resident in the Cocody neighborhood where Gbagbo lives in Abidjan said he saw multiple helicopters circling and could hear firing. Others said they heard what sounded like fighter jets.

French President Nicolas Sarkozy said in a statement that he had authorized the 1,600-strong French Licorne force based here to help in the operation following an appeal from U.N. Secretary-General Ban Ki-moon, who said that the use of force was necessary to prevent further attacks on civilians.

Ivory Coast gained independence from France in 1960, and some 20,000 French citizens still lived there when a brief civil war broke out in 2002. French troops were then tasked by the U.N. with monitoring a cease-fire and protecting foreign nationals in Ivory Coast, which was once an economic star and is still one of the only countries in the region with four-lane highways, skyscrapers, escalators and wine bars.

Following four months of attempts to negotiate Gbagbo's departure, the U.N. Security Council unanimously passed an especially strong resolution giving the 12,000-strong peacekeeping operation the right "to use all necessary means to carry out its mandate to protect civilians under imminent threat of physical violence ... including to prevent the use of heavy weapons against the civilian population."

Gbagbo, 65, has stubbornly refused every olive branch extended to him since last November, when he lost the presidential election to International Monetary Fund economist, Ouattara. Gbagbo insisted he had won, even though his country's own election commission declared him defeated and the United Nations certified his opponent's victory.

Many people in Abidjan have not left their homes since last Wednesday, when Ouattara's fighters arrived on the perimeter of the city, and heavy clashes ensued.

Barricaded inside her home, new mother Joceline Djaha, 24, said by telephone that she had stopped eating two days ago, when her stock ran out. For several days, her only food was boiled spaghetti — no sauce.

In the two days since she's been out of food, her breastmilk dried up. Her 1-year-old, she says, has become listless.
"Please let this stop," said Djaha. "I can hold out without food. But I'm not sure my child can."

Doctors Without Borders issued an urgent appeal Monday night for all warring factions to allow people to reach medical care.
In a statement, the organization said a team of its doctors had been trapped since Thursday "due to the extremely dangerous conditions" at the only hospital still functioning in the northern half of the city, which includes Gbagbo's residence.
They were treating 30 to 40 injured people daily, who made their way to the hospital by cart or other means, but gunfire and looting prevented helping others.

"We get telephone calls asking us to come pick up wounded people and patients, but it's impossible to move around," said Dr. Sal-ha Issoufou, head of the doctors' mission in Abidjan.