The UN humanitarian chief voiced alarm Wednesday at the prospect of Israel’s war against Hamas in Gaza spreading to Lebanon, warning that it was “potentially apocalyptic.”

As the war in Gaza nears its 10th month, Israel’s top ally the United States has warned of the risk of a major conflict against the Iran-backed militant group Hezbollah in Lebanon following an escalation in cross-border fire.

Martin Griffiths, the UN humanitarian coordinator, told reporters in Geneva that he saw Lebanon as “the flashpoint beyond all flashpoints”, pointing to southern Lebanon in particular.

He said he had been discussing with colleagues in Jerusalem about the prospects of what might happen there.

“It’s beyond planning. It’s potentially apocalyptic,” he said.

Griffiths, whose term finishes this week, warned that a war involving Lebanon “will draw in Syria... it will draw in others.”

And “it will of course have an impact on Gaza; of course, it will have an impact on the West Bank.”

“It’s very alarming,” he said.

Since the war in Gaza erupted nearly nine months ago following Hamas’s unprecedented attack inside Israel, it “has taught us a new level of tragedy and cruelty”, Griffiths said.

“But we are all worried that it may only be the beginning.”

The bloodiest-ever Gaza war started with Hamas’s October 7 attack on southern Israel that resulted in the deaths of 1,195 people, mostly civilians, according to an AFP tally based on Israeli figures.

The militants also seized about 250 hostages, 116 of whom remain in Gaza although the army says 42 are dead.

Israel’s retaliatory offensive has killed at least 37,658 people, also mostly civilians, Gaza’s health ministry has said.