The increased flow and vital port improvements have produced a 20 percent jump in exports this year to nearly 2.5 million barrels of oil a day, making Iraq one of the premier producers in OPEC for the first time in decades.

Energy analysts say that the Iraqi boom — coupled with increased production in Saudi Arabia and the near total recovery of Libya’s oil industry — should cushion oil markets from price spikes and give the international community additional leverage over Iran when new sanctions take effect in July.

“Iraq helps enormously,” said David L. Goldwyn, the former State Department coordinator for international energy affairs in the Obama administration. Even if Iraq increased its oil exports by only half of what it is projecting by next year, he said, “You would be replacing nearly half of the future Iranian supply potentially displaced by tighter sanctions.”