Moscow has repeatedly called on Washington to influence Syrian rebels to distance themselve fromn al-Nusra terrorists.
"We have accurate information that 617 militants have been killed since the beginning of the month, of whom dozens are leaders," Nasrallah said in an address broadcast by the Al Manar station.
Hezbollah, established in the 1980s, is a paramilitary and political organization originating in Lebanon's Shiite population. The group initially aimed to end Israel's occupation of Southern Lebanon. On May 25, 2000, Israel withdrew from Lebanon, which Hezbollah widely saw as its victory.