Former war cabinet member Benny Gantz on Sunday said Israel should shift its focus toward Hezbollah and the Lebanese border, warning that "we are late on this."

Israel and Iran-backed Hezbollah have been trading near-daily cross-border fire, with the Lebanese militant group saying it is acting in support of its Palestinian ally Hamas in the ongoing war in Gaza.

"We have enough forces to deal with Gaza and we should concentrate on what is going on in the north," Gantz said, speaking in Washington at a Middle East forum where he also said Iran and its proxies were "the real issue."

"The time of the north has come and actually I think we are late on this," the former army chief and centrist politician added.

Gantz said Israel had made a mistake in evacuating much of the north of the country as hostilities with Hezbollah flared following the October 7 Hamas attack that triggered the Gaza war.

"In Gaza, we have crossed a decisive point of the campaign," he said. "We can conduct anything we want in Gaza."

"We should seek to have a deal to get out our hostages but if we cannot in the coming time, a few days or few weeks, or whatever it is, we should go up north."

"We are capable of... hitting the state of Lebanon if needed," he said.

"The story of Hamas is old news," he added, saying instead that "the story of Iran and its proxies all around the area and what they are trying to do is the real issue."

Gantz left Prime Minister Benjamin Netanyahu's government in June over its lack of a post-war plan for Gaza.

The October 7 Hamas attack on Israel resulted in the deaths of 1,205 people, mostly civilians, including some hostages killed in captivity, official Israeli figures show.

Militants seized 251 hostages during the attack, 97 of whom are still held in Gaza, including 33 the Israeli military says are dead.

Israel's retaliatory offensive in Gaza has so far killed at least 40,972 people, according to the health ministry in the Hamas-run territory.

The UN human rights office says most of the dead are women and children.

Israeli Defence Minister Yoav Gallant also referred to the situation on the Lebanese border Sunday during a tour of the Netzarim Corridor in central Gaza, telling troops "we are preparing for anything that may happen in the north."

"The shift of the centre of gravity can happen quickly and can also involve you in a short period of time," Gallant said, according to a statement issued by his office.