UPDATE 2-Iraq, Eni-led group sign initial Zubair oil deal

* Oil Ministry says expects $35 bln in investment in Zubair

* Expects initial deal for Nassiriya in coming days

* Final Pact with BP-led group for Rumaila on Tuesday

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By Ahmed Rasheed

BAGHDAD, Nov 2 (Reuters) - Iraq's Oil Ministry signed an initial agreement on Monday with a consortium led by Italian oil major Eni to develop Zubair oilfield and said it also expected to ink a pact on Nassiriya in the coming days.

Iraq, emerging from years of violence triggered by the 2003 U.S. invasion, is seeking investment to help its energy sector overcome decades of war, sanctions and underinvestment and turn itself into the world's third largest crude producer.

Investors face considerable political risk. An election is due in January and there is no guarantee the next Iraqi government will honour any deals being struck now.

"Iraq is taking an important step to develop its oil industry by signing the many contracts we are about to sign," Oil Minister Hussain al-Shahristani said.

Eni has said it and its partners Occidental Petroleum Corp and South Korea's KOGAS expect to invest $10 billion in the field to ramp up production to 1.125 million barrels per day from 195,000 bpd within seven years.

But Shahristani said he expected the ENI-led group to invest $35 billion over six years in the 4-billion-barrel oilfield -- $20 billion in capital and $15 billion in operating expenses.

Depending on how quickly the agreement is approved by the Iraqi cabinet and a final deal worked out, Zubair is likely to become Iraq's second major new contract with an international oil firm since the invasion.

The Oil Ministry has already reached a final agreement with BP Plc and China's CNPC to develop the Rumaila oilfield, a 17-billion-barrel supergiant that accounts for around half of Iraq's current crude output.

The final contract for Rumaila will be signed on Tuesday.

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