Russian jets are flying some 25 bombing raids daily to back up a Syrian government offensive to recapture the ancient city of Palmyra from Islamic State jihadists, the armed forces said Friday.   

"Government troops and patriotic forces with the support of the Russian air force are carrying out a large-scale operation to liberate Palmyra," senior commander Sergei Rudskoi told journalists, adding that "on average Russian planes are flying 20 to 25 combat sorties each day."