The previously announced loans will be earmarked to reconstruction projects conducted by Iranian companies, Deputy Iranian Foreign Minister Ali Reza Sheikh Attar told the official IRNA news agency late Friday.
The money "was among the main issues discussed with the Iraqi side," Attar said, as he ended a visit to Baghdad as part of a delegation paving the way for Ahmadinejad's visit, due to begin Sunday.
Some 10 other economic cooperation agreements are expected to be signed between Iran and Iraq during Ahmadinejad's visit. The trip will be the first official visit by an Iranian head of state to Iraq.
Iran's relationship with Iraq has concerned the U.S., which accuses Tehran of aiding Shiite Muslim militias in Iraq that target U.S. troops. Iran has denied those allegations, saying its interests are better served if Iraq, a fellow Shiite-majority country, is stable.
"The political aim of the president's visit is to materialize the idea of establishing durable peace borders between Iran and Iraq," IRNA quoted Attar as saying.
The Iranian president also plans to inaugurate two power lines during his trip, Deputy Energy Minister Mohammad Ahmadian said.
He said one 400-megawatt electricity transmission line would run from the Iranian port city of Abadan to the Iraqi town of Alharasa, and another from Iran's Marivan to Panjwin in Iraq.