By Idrees Ali and Doina Chiacu
WASHINGTON (Reuters) - U.S. led air strikes in Syria have inflicted "significant damage" to Islamic State's ability to fund itself, the Pentagon said on Friday.
Recent strikes in an air operation dubbed "Tidal Wave II" have been concentrated on oil facilities in the Dayr Az Zawr region, which provide an estimated two-thirds of Islamic State's oil revenue, Pentagon spokesman Col. Steve Warren said at a news briefing.
"We believe that by cutting off its oil supply we could hasten the destruction of ISIL," Warren said, using an acronym for Islamic State.
The first strike in the coalition operation was on the Omar oil field on Oct. 21 and since then airstrikes have been stepped up, Warren said.
Warren said the strikes, halfway through the Tidal Wave operation, have inflicted "significant damage" on the militant group's ability to fund itself.
While airstrikes have targeted oil facilities in the past, Warren said they were against parts that were being easily repaired or replaced.
"So we did a detailed analysis to determine how can we strike the oil field to break them for longer, essentially," he said.
The aim is not to completely destroy the oil facilities, but to shut down them down for longer periods of time, Warren added.
“There will be a time after the war, the war will end, so we don't want to completely and utterly destroy these facilities to where they are irreparable,” he said.
Oil revenue is one of the largest sources of income for the Islamic State and the operation could have a significant impact on the terrorist organization, according to Frederic Hof, a senior fellow at the Atlantic Council think tank.
"This is very much a revenue-decreasing operation, designed to eliminate, what I understand to be a very significant source of revenue for ISIS,” Hof said, using a different acronym for the group.
(Reporting by Doina Chiacu and Idrees Ali; Editing by David Alexander and Andrea Ricci)