The leader of the Hezbollah militant group has thrown his backing behind Palestinian militants and praised the attacks that killed more than a thousand Israeli civilians, in his first public appearance since the start of the war between Israel and Hamas last month.

In a televised speech broadcast on Friday from an unknown location, Hassan Nasrallah praised the “martyrs” who have died fighting Israeli troops, denied the Hamas attacks had been coordinated by Iran, and said fighters loyal to him were “prepared to make unlimited sacrifices” in supporting their cause.

“This operation is great; this sacred operation was 100 percent Palestinian, and was implemented by Palestinians,” he said. 

However, he stopped short of explicitly declaring war on Israel and opening a second front in the conflict, despite predictions that he could seek to escalate tensions dramatically.

Nasrallah has led Hezbollah since 1992, when his predecessor was killed by Israeli forces. While the group maintains it is comprised of both a political party and a separate military wing, Hezbollah has been designated as a terrorist organization in its entirety by Israel, the U.S., the U.K., the Arab League and a number of EU member states. It has close ties to Iran, which also backs Hamas in the Gaza Strip, as well as the government of Bashar al-Assad in Syria and paramilitaries in Iraq and Yemen — all of which are vehemently opposed to Israel and its Western partners.

Hezbollah maintains a tight hold over southern Lebanon, effectively ruling the region independently from the Middle Eastern nation’s elected government. Its fighters have carried out attacks and drone strikes on Israeli positions across the line of contact in recent days amid a sharp spike in violence across the region, with Israeli officials ordering the evacuation of citizens from 42 communities in the surrounding area.

Ahead of Nasrallah’s speech, schools and government buildings throughout Lebanon closed and crowds gathered in the capital of Beirut as well as in other Middle Eastern countries to watch the address. While many in the tiny nation — home to just five and a half million people — fear a renewed conflict with Israel, Hezbollah is effectively able to operate entirely independently from the state and retains high levels of support from the Shia Muslim community.

The Israel Defense Forces earlier Friday said it was on “very, very high alert” along its northern border with Lebanon.

Southern Lebanon was effectively occupied by Israeli forces from 1985 until 2000, fighting a series of military offensives and running battles with militant groups during and after the country’s 15-year civil war. Hezbollah and Israel also fought a brief but bloody war in 2006, with hundreds killed on both sides and no decisive result.

French Armed Forces Minister Sébastien Lecornu was in Beirut Friday afternoon, declaring that his country “will continue to provide support to the Lebanese Armed Forces … because the stability of Lebanon is key for the country and for the region.”

Meanwhile, U.S. Secretary of State Antony Blinken is in Israel amid growing calls for a “humanitarian pause” in the fighting to allow Palestinian civilians to flee as Israel steps up its offensive in the Gaza Strip. Blinken reiterated Israel’s right to defend itself and said “no country would, or should, tolerate the slaughter of innocents.” However, he did call for greater protection for Palestinians amid the worsening military confrontation.

The Hamas-run Health Ministry in Gaza claims that 9,000 people have been killed since the start of the conflict last month, while Israeli troops have taken control of key strategic points in and around Gaza City, telling non-combatants to leave their homes and seek safety in southern Gaza — which has also been targeted by air strikes.

More than 1,400 people have been killed on the Israeli side of the border since Hamas launched its major offensive, with fighters infiltrating the country by land, air and sea.

Laura Kayali contributed reporting.