U.S.-backed Arab-Kurdish forces will "very soon" launch their campaign to liberate Raqqa, the Islamic State (IS) militant group's self-declared capital in Syria.
Spokeswoman Cihan Sheikh Ehmed of the U.S.-supported Syrian Democratic Forces on June 3 said the SDF will "very soon" begin the battle for Raqqa, which is situated on the northern side of the Euphrates River about 90 kilometers from the Turkish border.
The comments come at a time when U.S.-backed Iraqi government forces say they are close to fully liberating Mosul, the final significant IS stronghold in Iraq.
IS fighters captured wide swathes of land in Syria and Iraq in 2014 in battles against government troops.
U.S.-led coalition forces in both countries have made major gains against the group, which is putting up fierce resistance as it clings to the last bits of territory in its so-called "caliphate" in the region.
The SDF fighters have taken positions around Raqqa ‘s northern and eastern sectors and report they are making progress against IS extremists on the south bank of the Euphrates.
Nouri Mahmoud, a spokesman for the YPG -- a Syrian Kurdish militia that is a key element of the SDF coalition -- told Reuters news agency that "forces reached the outskirts of the city and the major operation will start...in the coming few days."
A spokesman for the U.S.-led coalition, Colonel Ryan Dillon, would not confirm the time frame but said SDF fighters were "advancing closer and closer every day" and were within 3 kilometers of Raqqa.
Coalition officials estimate there are 3,000 to 4,000 IS fighters remaining in Raqqa preparing for the assault.
"The battle will not be easy," the YPG’s Mahmoud said. "Of course, [IS] has tunnels, mines, car bombs, suicide bombers, and at the same time it is using civilians as human shields."
Along with the battle against IS, Syria is embroiled in a six-year civil war. Russia and Iran support the government of President Bashar al-Assad, while the United States and Turkey back differing rebel groups.
Turkey is opposed to the YPG, which it links to the Kurdistan Workers Party (PKK).