BEIRUT — Syrian President Bashar Assad said in an interview broadcast Thursday he is “confident in victory” in his country’s civil war, and he warned that Damascus would retaliate for any future Israeli airstrike on his territory.

Assad also told the Lebanese TV station Al-Manar that Russia has fulfilled some of its weapons contracts recently, but he was vague on whether this included advanced S-300 air defense systems.

The comments were in line with a forceful and confident message the regime has been sending in recent days, even as the international community attempts to launch a peace conference in Geneva, possibly next month. The strong tone coincided with recent military victories in battles with armed rebels trying to topple him.

The interview was broadcast as Syria’s main political opposition group appeared to fall into growing disarray.

The international community had hoped the two sides would start talks on a political transition. However, the opposition group, the Syrian National Coalition, said earlier Thursday that it would not attend a conference.

Assad, who appeared animated and gestured frequently in the TV interview, said he has been confident from the start of the conflict more than two years ago that he would be able to defeat his opponents. “Regarding my confidence about victory, had we not had this confidence, we wouldn’t have been able to fight in this battle for two years, facing an international attack,” he said. Assad portrayed the battle to unseat him as a “world war against Syria and the resistance” — a reference to the Lebanese Hezbollah, a close ally.

Assad has said he would stay in power at least until elections scheduled in 2014, but he went further in the interview, saying he “will not hesitate to run again” if the Syrian people want him to do so.

Taking a tough line, he also warned that Syria would strike back hard against any future Israeli airstrike. Earlier this month, Israel had struck near Damascus, targeting suspected shipments of advanced weapons purportedly intended for Hezbollah. Syria did not respond at the time.

Assad said he has informed other countries that Syria would respond next time. “If we are going to retaliate against Israel, this retaliation should be a strategic response,” he said.

Russia’s S-300 missiles would significantly boost Syria’s air defenses and are seen as a game-changer, but Assad was unclear whether Syria has received a first shipment. The U.S. and Israel had urged Russia to cancel the sale, but Russia rejected the appeals.

More than 70,000 people have been killed in the 26-month-old Syrian conflict.