General Richard Myers, the chairman of the Joint Chiefs of Staff, insisted "this notion of a siege and so forth, I think is not the right mental picture," but the scenario he outlined was one in which US forces would cut off the Iraqi regime inside the city and render it powerless.

"So you're going to have Baghdad isolated," he said. "You're going to have half the population that probably wants nothing to do with the ... regime. And then you'll start working at it as you can. But one of the things you can do is be patient about that."

US Defense Secretary Donald Rumsfeld, meanwhile, lashed out at unnamed third countries who he said have been encouraging the Iraqi regime to "cut a deal," saying that would only give it hope and comfort that it could survive as it did 12 years ago after the Gulf war.

"There's not a chance that there is going to be a deal," Rumsfeld told reporters.

In the view of many analysts, the Iraqi regime may be counting on international revulsion at the prospect of bloody urban warfare and rising civilian casualties to force a settlement of the conflict.

US forces were reported to be 15 kilometers (nine miles) from downtown Baghdad after rolling through bomb-shattered Republican Guard divisions that formed the city's outer defense lines.

Myers and Rumsfeld indicated that the Republican Guard were in disarray, and not making a strategic retreat into the city to draw US forces in behind them.

Some Iraqi forces have dispersed, sometimes with their equipment, but US troops were careful not to go into areas where they could be enveloped, Myers said.

"A lot of the people have been killed, a lot of the people that come out after dark to attack our tanks that might be lying in the shadows. The death squads and those sorts of folks -- a lot of them have been killed as well," Myers said.

Some Iraqi forces have retreated into the city and melted away, while others have surrendered and still others continued to fight, they said.

But Myers said the primary effort appeared to be to reinforce the Republican Guard units that have been decimated.

"The regime has been weakened to be sure, but it is still lethal, and it may prove to be more lethal in the final moments before it ends," Rumsfeld said.

Rumsfeld and other senior defense official appeared unsure to what extent the regime retains control over its forces.

Major General Stanley McChrystal, vice director of operations of the Joint Staff, noted that historically the Republican Guard has not been trusted to go into Baghdad.

"We're not sure, quite honestly whether that is the strategy. We're not sure whether the command and control of the regime at this point is such that it can make decisions," he said.

Myers indicated that coalition forces will try to break off the predominantly Shiite eastern areas of the city.

"When you get to the point where Baghdad is basically isolated, then what is the situation you have in the country? You have a country that Baghdad no longer controls, that whatever's happening inside Baghdad is almost irrelevant compared to what's going on in the rest of the country," he said.

"What's going on in the rest of the country? Well, you have the southern oil fields. We'll see about the north. You have the face now by this time probably of an Iraqi interim administration, some form of people standing up now starting to work the post-conflict governance," he said.

WAR.WIRE