US commanders have been trumpeting how tribesmen have fought alongside coalition troops in the drive to topple the Iraqi leader while also teaming up with Kurdish rebel fighters in the north.

But Joost Hiltermann, Middle East project director of the International Crisis Group think tank, said the United States risked causing post-war instability, as local leaders now lining up alongside the coalition could themselves have blood on their hands.

"Even if they have clean hands, if you start playing politics by going into an alliance with one (tribe) but not another, that's going to have consequences in the post-Saddam Iraq," Hiltermann told AFP.

"It's not like we can get around the tribes. We will have to deal with them. But if you form tactical alliances you are playing them politically and there's a cost involved."

With the United States determined to have a major influence in the shape of a post-Saddam regime in Baghdad, Hiltermann warned that the "empowerment" of one tribe over another "will not serve Iraq well in the long-term".

Coalition war planners had been hoping that Iraqis would spontaneously rise up against Saddam and his ruling Baath party henchmen when they became convinced that his regime was doomed.

But the failure of a large-scale revolt to so far materialise even in the main southern city of Basra, where opposition to Saddam has traditionally been most fierce, appears to have pushed the coalition to seek out allies.

Some 100 tribesmen had joined up with the marines in attacks near the southern towns of Diwaniyah and Shatra, Brigadier General Vincent Brooks told reporters earlier this week.

But Hiltermann said that tribal leaders now willing to see off the Iraqi strongman could turn out to be "complicit in the crimes" during Saddam's 24-year rule, complicating any attempts to bring perpetrators of abuses to justice.

In the north, US special forces have also been teaming up with Kurdish fighters from the Patriotic Union of Kurdistan (PUK) in the campaign against Saddam.

The US pointman for contacts with the Iraqi opposition groups is Zalmay Khalilzad, who served as President George W. Bush's special envoy to Afghanistan.

In his former role, Khalilzad defended US links with regional strongmen in Afghanistan, insisting that such alliances were the best way of crushing Taliban and Al-Qaeda resistance.

But many observers fear such alliances have worked against attempts to build up the authority of the central government in Kabul, while also providing a degree of protection to warlords accused of perpertrating abuses.

Turkey fears that the Iraqi Kurds -- capitalizing on their alliance with the United States against Baghdad -- might move towards independence, setting an example for their restive kinsmen in adjoining southeast Turkey.

"The United States has to take measures against possible developments in the region with an approach taking into account Turkey's sensitivities," said a recent meeting of Turkey's National Security Council, which brings together the top civilian and military officials.

After two dozen years of iron-fisted rule by Saddam, the coalition is struggling to find reputable or credible opposition figures to work with not only in the war but in relief operations as well.

British Major General Albert Whitley, deputy commander of post hostility operations, has admitted that the coalition has struggled to find Iraqis to work with in coordinating aid efforts.

"What we intend to do ... is to work with those Iraqis with whom we can work," said Whitley. "We are not there yet."

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