Russian state energy monopoly Lukoil will invest 30 billion U.S. dollars with its foreign partners in the development of the West Qurna-2 oil field in Iraq, said the company's CEO Monday.

First phase of investment to the oil field, whose annual output is estimated at 95 million metric tons, will reach 4.5 billion dollars, said Vagit Alekperov when meeting with Prime Minister Vladimir Putin.

Russia has canceled more than 10 billion dollars, or 90 percent of the debt owed to it by Iraq, said Putin, adding that the Iraqi government has welcomed Lukoil's move.

It was also "a pleasure" for Lukoil and Norwegian Norsk Statoil to win the tender for the West Qurna-2 in last December, he said.

An agreement signed on Sunday between Lukoil, Norsk Statoil and the Iraqi government stipulated a 56.25 percent share for Lukoil, 18.75 percent for Norsk Statoil, and 25 percent for Iraqi North Oil Company.

Located in southern Iraq, the West Qurna-2 oil field has a known deposit of 12.9 billion barrels.