Ahmadinejad's Iraq visit underlines Iran's growing role

By Michael Holden

BAGHDAD (Reuters) - President Mahmoud Ahmadinejad will make history when he arrives in Baghdad on Sunday, the first Iranian president to step foot in Iraq on a trip many see as symbolic of Tehran's new influence over its old foe.

Iranian sway over Baghdad has grown substantially since the 2003 U.S.-led invasion ousted Tehran's long-time enemy Saddam Hussein and his ruling Sunni Baath party against whom it fought an eight-year war in the 1980s.

But just how far this influence extends is far from clear.

Some experts argue that Tehran wants to dominate its neighbour, wielding political, economic and religious control. Others say it neither desires nor is able to achieve such ends.

The evidence is inconclusive and murky, mirroring the often opaque nature of Iranian politics itself.

"Iran has the ability to destabilise the political situation in Iraq by triggering violence, by supporting and arming some militia and through its influence on the Iraqi government," said Hasan al-Shimmari, head of Iraq's small Shi'ite Fadhila Party.

"The political system in Iraq is not mature enough yet. It gives a chance for Iran to interfere in Iraqi matters."

U.S. officials say Iran exerts considerable influence over Shi'ite cleric Moqtada al-Sadr, who has a large following among Iraq's Shi'ite poor and commands a powerful militia, the Mehdi Army. Tehran is widely believed to have been behind ceasefires called by Sadr in August and again this month.