WASHINGTON • The US-led coalition fighting the Islamic State in Iraq and Syria (ISIS) has begun preparing to open a major front in north-eastern Syria, aiming to put pressure on Raqqa, the terrorist group's de facto capital, according to military and administration officials.
United States President Barack Obama last week approved two important steps to set the offensive in motion over the coming weeks, officials said. He ordered the Pentagon, for the first time, to directly provide ammunition and perhaps some weapons to Syrian opposition forces on the ground.
He also endorsed the idea for an increased air campaign from an air base in Turkey, although important details still need to be worked out.
Together, these measures are intended to empower 3,000 to 5,000 Arab fighters who would join more than 20,000 Kurdish combatants in an offensive backed by dozens of coalition warplanes to pressure Raqqa.
Plans are also moving forward to have Syrian opposition fighters seal an important 96km part of the country's border with Turkey to cut off critical ISIS supply lines.
As recently as last Friday, Mr Obama said he would take all steps necessary to combat ISIS.
The new approach relies on Arab fighters whose commanders have been screened by US forces and Kurdish fighters who are more battle-tested and whose loyalties Washington can count on.
"The top-line message that I want everybody to understand is, we are going to continue to go after ISIS," Mr Obama told reporters. "We are going to continue to reach out to a moderate opposition."
The new US-led push would be conducted far from the brunt of the Russian air campaign in western Syria. That Russian operation has been directed largely at Syrian groups opposing President Bashar al-Assad, and is only nominally aimed at ISIS, US officials said.
The new northern front would be the opposite: It is entirely directed at weakening ISIS by trying to take away the group's home-court advantage, even as the militants hold on to Mosul and Ramadi in Iraq and Palmyra in Syria.
Even in describing the goals of the campaign, officials said they would not disclose the kinds of details that might help ISIS anticipate exactly how the offensive would unfold.
The administration's plan is to support the Kurdish and Arab fighters and have them advance towards Raqqa, but not try to seize the heavily defended city itself.
Rather, the aim is to isolate Raqqa and cut it off from travel and supply lines north-east and north-west of the city.
Under planning for the northern offensive, coalition air power at the Incirlik air base in Turkey would also be expanded.
Meanwhile, French Foreign Minister Laurent Fabius said yesterday that air strikes in Syria must target ISIS militants, but also other groups "considered as terrorists."
He said a statement by President Francois Hollande last Friday that Russian air strikes must target "Daesh and only Daesh (the Arabic acronym for ISIS)", did not exclude other groups like the Al-Nusra Front.
"Of course, it is a concise formulation, it is Daesh and groups considered as terrorists," Mr Fabius told Europe 1 radio in an interview, referring to Mr Hollande's statement.
Moscow, which has launched more than 70 air strikes in Syria since last Wednesday, has come under fire for targeting Western-backed moderate opposition and ISIS fighters alike in their bid to bolster President Assad.
In a related incident, two Turkish F-16 jets were harassed by an unidentified MIG-29 aircraft on the Syrian border a day after a Russian fighter plane violated Turkish airspace, the military said yesterday.
"Two F-16 jets were harassed by a MIG-29 plane - whose nationality could not be identified - for a total of five minutes and 40 seconds," the army said in a statement, adding that the incident took place on Sunday.
Turkey said earlier that its F-16 jets had, on Saturday, intercepted a Russian fighter plane which violated Turkish air space near the Syrian border, forcing the aircraft to turn back.
Turkey summoned the Russian ambassador in Ankara to the foreign ministry and "strongly protested" the violation, the Turkish foreign ministry said in a statement.
The ministry demanded that "any such violation not be repeated", otherwise Russia "will be responsible for any undesired incident that may occur".
NEW YORK TIMES, AGENCE FRANCE-PRESSE