Israel was on high alert for an escalation with Hezbollah on Wednesday after one of the top leaders of the Palestinian Hamas was killed in a strike in Beirut that was widely blamed on Israel and heightened the risk of a broader Middle East conflict.

The killing of Saleh Arouri, the most senior Hamas member slain since the war in Gaza erupted nearly three months ago, provided a morale boost for Israelis still reeling from Hamas' October 7 attack as the militants put up stiff resistance in Gaza and continue to hold scores of hostages.

But its implications for the war remain unclear. Israel has killed several top Hamas leaders over the years, only to see them quickly replaced. And the strike in Hezbollah's southern Beirut stronghold could cause the low-intensity fighting along the Lebanon border to boil over into all-out war.

Much depends on how Hassan Nasrallah — who has led Hezbollah since an Israeli strike killed his predecessor in 1992 — chooses to respond. He has previously vowed to retaliate for any Israeli targeting of allied militant leaders in Lebanon, and was expected to deliver a speech at 6 p.m. (1600 GMT).

Hezbollah and the Israeli military have been exchanging fire almost daily over the Israeli-Lebanese border since the war in Gaza began, but Nasrallah has appeared reluctant to escalate it further, perhaps fearing a repeat of the monthlong 2006 war, in which Israel heavily bombed Beirut and southern Lebanon.

Israeli officials have not commented on the strike that killed Arouri, but Rear Adm. Daniel Hagari, an Israeli military spokesman, said “we are on high readiness for any scenario.”

The United States has sought to prevent any widening of the conflict, including by deploying two aircraft carriers and other military assets to the region. Secretary of State Antony Blinken was expected in the region this week.

A HIGH-PROFILE TARGET

Prime Minister Benjamin Netanyahu and other Israeli officials have repeatedly threatened to kill Hamas leaders wherever they are. The group's October 7 attack from Gaza into southern Israel killed around 1,200 people, and some 240 others were taken hostage.

Israel claims to have killed a number of mid-level Hamas leaders in Gaza, but this would be the first time since the war that it has reached into another country to target the group's top leaders, many of whom live in exile around the region.

Arouri was the deputy of Hamas' supreme political leader, Ismail Haniyeh, and headed the group's presence in the Israeli-occupied West Bank. He was also a key liaison with Hezbollah. The US State Department had listed him as a terrorist and offered a USD 5 million reward for information about him.

Haniyeh said Hamas was “more powerful and determined” following the attack, which killed six other members of the group, including two military commanders. “They left behind them strong men who will carry the banner after them,” he said of those killed.

Hezbollah called the strike “a serious attack on Lebanon, its people, its security, sovereignty and resistance.”

“We affirm that this crime will never pass without response and punishment,” it said.

ISRAEL SEEKS A 'CLEAR VICTORY' IN GAZA

The focus of the war remains on Gaza, where Israeli Defence Minister Yoav Gallant said Israel is seeking a “clear victory” over Hamas, which has ruled the territory since 2007.

Israel's air, ground and sea assault in Gaza has killed more than 22,300 people, two-thirds of them women and children, according to the Health Ministry in the Hamas-ruled territory. The count does not differentiate between civilians and combatants.

The campaign has driven some 85 per cent of Gaza's population from their homes, forcing hundreds of thousands of people into overcrowded shelters or teeming tent camps in Israeli-designated safe areas that the military has nevertheless bombed. A quarter of Gaza's population face starvation, according to the United Nations, as Israeli restrictions and heavy fighting hinder aid delivery.

The unprecedented death and destruction has led South Africa to accuse Israel of genocide in a case filed with the International Court of Justice, allegations Israel has strongly denied and vowed to contest.

Still, Israel appears far from achieving its goals of crushing Hamas and returning the estimated 129 hostages still held by the group after more than 100 were released in a cease-fire deal in November.

Gallant said several thousand Hamas fighters remain in northern Gaza, where Israeli troops have been battling militants for over two months and where entire neighbourhoods have been blasted into rubble.

Heavy fighting is also underway in central Gaza and the southern city of Khan Younis, where Israeli officials say Hamas' military structure is still largely intact. Yehya Sinwar, Hamas' top leader in Gaza, and his deputies have thus far eluded Israeli forces.

Egypt, which along with Qatar has served as a mediator between Israel and Hamas, has proposed a multistage plan for ending the war in which all hostages would eventually be released in exchange for Palestinians imprisoned by Israel. Israel would withdraw from Gaza and a government of Palestinian technocrats would govern Gaza and parts of the occupied West Bank until elections are held.

Neither Israel nor Hamas have accepted the plan in its entirety, but neither has rejected it outright.

An Israeli delegation was in Cairo on Wednesday to discuss the proposal, according to an Egyptian official who was not authorised to brief media and spoke on condition of anonymity. The official said the killing of Arouri was likely to hamper the negotiations for a couple days.