Sayyed Hassan Nasrallah, the leader of the Iran-backed Lebanon-based group Hizballah, which has been designated a terrorist organization by the United States, said Israel's recent actions will not go without a "strong and effective" response amid fears of a full-blown war in the region.
Hizballah said six of its fighters were killed in Israeli attacks on August 6, while it claimed to have launched missiles and drones at Israel, though no casualties were immediately reported.
For months, Israel and Hizballah have traded constant cross-border attacks -- including a deadly rocket attack from Lebanon on July 27 that hit the Israeli-occupied Golan Heights, killing 12 youths and children -- that have killed many and displaced thousands of people.
Pressure has continued to build since strikes killed top military commander Fuad Shukr in a Beirut suburb and Ismail Haniyeh, the political leader of Hamas, which has also been designated a terrorist organization by the United States and the European Union, in Iran.
Tehran is Hizballah's main ally, and the Lebanese militant group is a key member of Iran's so-called axis of resistance, a loose network of militant groups and proxies that aid it in opposing Israel and the United States.
Hizballah is also considered a key part of Iran's efforts to deter Israel or Washington from going to war against Tehran.
Tehran "finds itself obliged to respond, and the enemy is waiting in a great state of dread," Nasrallah said in a televised address on August 6 to mark one week since Shukr's death.
“Whatever the consequences, the resistance will not let these Israeli attacks pass by," he added, saying that Hizballah will respond "alone or in the context of a unified response from all the axis" of Iran-backed groups in the region, "whatever the consequences."
Experts say no side wants an all-out war in a region that has been reeling since Israel launched its war against Hamas after it killed some 1,200 people in a raid and took 240 people hostage on October 7.
SEE ALSO: What Hamas Leader's Killing Means For Talks Aimed At Ending Gaza WarHizballah has not usually shied away from claiming attacks on Israeli targets. But it issued a rare denial of responsibility after the attack that killed the children and youths in the Golan Heights.
Israel has not claimed responsibility for the two recent assassinations, but it has admitted to killing other senior Hamas leaders, including Saleh al-Arouriand Mohammed Deif, the movement's military commander.
Hamidreza Azizi, a fellow at the German Institute for International and Security Affairs, recently told RFE/RL that if war did break out, members of the "axis of resistance" would likely intensify their attacks against Israel while also targeting U.S. troops and bases in the region in a bid to pressure Washington to rein in Israel.
U.S. Secretary of State Antony Blinken on August 5 called it a "critical moment" for the region and said Washington was "engaged in intense diplomacy, pretty much around the clock" to help calm tensions amid fears Iran is preparing a retaliatory strike against Israel over Haniyeh's assassination in the Iranian capital.
As the world waits to see how and when Iran carries out its promised response to Haniyeh's assassination, Hamas named its Gaza leader, Yahya Sinwar, as Haniyeh's successor.
Sinwar is considered the architect of the October 7 attack on Israel, and is believed to be in hiding in Gaza, evading Israeli attempts to kill him since the start of the war.