US-led action against Saddam Hussein's regime in Iraq would likely involve the help of internal and external opponents of the regime.
These include semi-autonomous Iraqi Kurdish groups in the north, Shia Muslim groups in the south, senior army officers who have defected, and the Iraqi National Congress (INC) which says it acts as an umbrella for numerous other exiled opposition groups.

BBC News Online examines the main opposition players.
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Iraqi National Congress
The Iraqi National Congress is the best known of the exiled Iraqi opposition groups.

It was founded in 1992 as an umbrella grouping of mainly Kurdish and Shia opposition members.

In its heyday, the INC had a stronghold and small army based in the US-protected Kurdish territory in northern Iraq.

It saw itself as a government in waiting and had influential friends in America.
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Iraqi National Accord

The Iraqi National Accord consists mainly of military and security defectors and supports the idea that the US should try to foster a coup from within the Iraqi army.
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Kurdistan Democratic Party and Patriotic Union of Kurdistan
The two main Kurdish parties operate in the Kurdistan Autonomous Region (KAR) of northern Iraq.

Between them they have about 40,000 troops and constitute the main armed threat to Saddam Hussein.
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Supreme Council for Islamic Revolution in Iraq
Along with the main Kurdish groups, the Supreme Council for Islamic Revolution in Iraq (SCIRI) is the main armed opposition to President Hussein.

It is made up of exiled members of Iraq's Shia community - which is based in the south and represents about 60% of Iraq's 22 million inhabitants.

The group enjoys the backing of Iran. Its spiritual and political leader, Mohammed Baquir al-Hakim, is based in Tehran.

» Who's who in Iraqi opposition