A US envoy said Monday that a diplomatic solution was key to ending nearly five months of intensifying hostilities between Lebanon's Hezbollah and Israel after the eruption of the Israel-Hamas war.

Israel and the Iran-backed Hezbollah movement have been exchanging near-daily fire since October, raising fears all-out conflict could spread across the region.

"A diplomatic solution is the only way to end the current hostilities" and achieve "a lasting fair security arrangement between Lebanon and Israel", Washington's envoy Amos Hochstein told reporters in Beirut, adding that "a temporary ceasefire is not enough".

"A limited war is not containable," he said after meeting with parliament speaker Nabih Berri, a Hezbollah ally.

Security along the Blue Line, demarcated by the United Nations in 2000 after Israeli troops pulled out of southern Lebanon, "has to change in order to guarantee everyone's security", he added.

Hochstein was set to hold talks with other senior officials including Prime Minister Najib Mikati in a push to halt violence along the border with Israel.

His visit came as Israeli medics said a missile from Lebanon killed a foreign worker near the border and wounded at least seven others, the latest casualties in months of escalating clashes.

Finding a diplomatic solution "is not just an American effort", Hochstein said, adding that Washington was working with "global partners... to advance opportunities for prosperity and stability in Lebanon".

He said there would be international support for Lebanon including its economy and military "but this can only start when we can reach a way forward".

Hezbollah's deputy chief Naim Qassem earlier Monday reiterated that the group, which says it is acting support of Gazans and Hamas, would stop its attacks on Israel once the Gaza offensive ends.

"Stop the assault on Gaza and war will end in the region," Qassem said of Israel's military campaign against Hamas.

Hochstein said the US was working "tirelessly" for a ceasefire in the Gaza Strip.

But Israeli Defence Minister Yoav Gallant has said there will be no let-up in Israeli action against Hezbollah even if a Gaza ceasefire is secured.

During a January visit, Hochstein had said both Lebanon and Israel "prefer" a diplomatic path to end hostilities.

The cross-border fighting has displaced tens of thousands on both sides and has killed at least 296 people in Lebanon, most of them Hezbollah fighters but also including 46 civilians, according to an AFP tally.

In Israel, at least 10 soldiers and seven civilians have been killed.