Hezbollah leader Naim Qassem on Monday rejected Lebanon's planned direct talks with Israel, calling them a "grave sin" that will destabilize Lebanon.

"We categorically reject direct negotiations with Israel, and those in power should know that their actions will not benefit Lebanon or themselves," Qassem said in a statement, calling on authorities to "back down from their grave sin that is putting Lebanon in a spiral of instability".

"These direct negotiations and their outcomes are as if they do not exist for us, and they do not concern us in the slightest," he added, saying "we will continue our defensive resistance for Lebanon and its people".

"No matter how much the enemy threatens, we will not back down, we will not bow down, and we will not be defeated."