Lebanon's Hezbollah chief Hassan Nasrallah on Friday will break weeks of silence since war broke out between Hamas and Israel, in a speech that could impact the region as the Gaza conflict rages.

After Hamas militants launched an unprecedented October 7 attack on Israel from the Gaza Strip, Lebanon's southern border has seen escalating tit-for-tat exchanges, mainly between Israel and Hezbollah, an ally of the Palestinian group, stoking fears of a broader conflagration.

The cross-border attacks heated up Thursday, as Israel responded with a "broad assault" after Hezbollah attacked 19 Israeli positions simultaneously, according to the group.

Rockets also hit the Israeli town of Kiryat Shmona near the border in a barrage claimed by the Lebanese section of Hamas's armed wing.

Iranian Foreign Minister Hossein Amir-Abdollahian has warned that "the region is like a powder keg" and that "anything is possible" if Israel does not stop attacking Gaza.

US President Joe Biden has sent two aircraft carrier groups to the eastern Mediterranean and warned Hezbollah and others to stay out of the conflict.

"We've got significant national security interests at play here," US National Security Council spokesman John Kirby told reporters.

"I don't believe we've seen any indication yet specifically that Hezbollah is ready to go in full force. So we'll see what he has to say."

Nasrallah's highly anticipated speech will be broadcast as part of an event in Beirut's southern suburbs, a Hezbollah stronghold, at 3:00 pm (1300 GMT) on Friday, in memory of fighters killed in Israeli bombardments.

On the Lebanese side, more than 70 people have been killed -- at least 50 of them Hezbollah fighters but also other combatants and civilians, one a Reuters journalist, according to an AFP tally.

On the Israeli side, nine people have died -- eight soldiers and one civilian, the army says.

- 'Red line' factors -

 

Some analysts believe that Hezbollah has little interest in becoming fully embroiled in a conflict that Israeli officials have threatened could destroy Lebanon.

Others say the decision lies with Iran, which leads the regional "axis of resistance" against Israel, which alongside Hezbollah includes armed groups from Syria, Iraq and Yemen, some of which have attacked Israel and US interests in the region in recent weeks.

But Amal Saad, a Hezbollah expert at Cardiff University, said: "Hezbollah is not a proxy of Iran, it's an ally of Iran... Hezbollah doesn't need anyone's permission to intervene."

"Hezbollah has much more experience obviously fighting Israel than Iran does -- Iran has not had a direct confrontation with Israel," Saad added.

Hezbollah on Wednesday published a letter from its fighters addressed to Palestinian groups in Gaza, saying they had their "finger with you on the trigger... to support Al-Aqsa mosque and our oppressed brothers in Palestine".

The Shiite Muslim group has mainly restricted itself to targeting Israeli observation posts, military positions and vehicles near the border as well as drones, using what it says have been anti-tank missiles, guided missiles and even surface-to-air missiles.

Israel has responded by bombing sites along the border, while drones have targeted fighters near the frontier.

The border tensions have revived memories of Hezbollah's devastating 2006 war with Israel that killed more than 1,200 people in Lebanon, mostly civilians, and 160 in Israel, largely soldiers.

- 'Death blow' warning -

 

Hezbollah receives financial support as well as weapons and equipment from Iran, and has built up its powerful arsenal since 2006.

For years, Nasrallah has boasted that his group's weapons could reach deep into Israeli territory.

"Each side is carefully measuring its actions and reactions to avoid a situation that may spin out of control and spread to the region," said Michael Young from the Carnegie Middle East Center.

But if Hezbollah fully entered the war, "Lebanon's devastation would turn most communities, perhaps even large segments of the Shiite community", against it, he warned last week.

In Lebanon, those both for and against expanding the war are holding their breath for Nasrallah's speech.

"We are waiting impatiently... We hope he will announce war on the Israeli enemy and the Western countries that support it," said Ahed Madi, 43, from the border town of Shebaa.

Rabih Awad, 41, from the southern town of Rashaya al-Fokhar, said a new war between Hezbollah and Israel "would be a death blow for Lebanon", which is grappling with a crushing economic crisis.

"I am against the war of extermination on the Palestinians in Gaza," he told AFP.

"But the decision to go to war must be taken by the Lebanese state, not a party or a militia."