Hezbollah chief Naim Qassem threatened Israel directly for the first time in months in a televised speech on Tuesday, saying missiles would fall on it if it resumed a broad war on Lebanon.

His comments came as Lebanon's cabinet met to discuss the fate of Hezbollah's arsenal, after Washington pressured Lebanese officials to commit to disarming the Iran-backed group and amid fears that Israel could intensify strikes if they fail to do so.

Qassem said that, should Israel engage in a "large-scale aggression" against Lebanon, Hezbollah, Lebanon's army and Lebanon's people would defend themselves.

"This defence will lead to missiles falling inside the Israeli entity, and all the security they have built over eight months will collapse within an hour," he said.

A U.S.-brokered ceasefire in November brought an end to months of fighting between Hezbollah and Israel. The war killed much of Hezbollah's leadership - including Qassem's predecessor Sayyed Hassan Nasrallah - and destroyed much of its arsenal.

Qassem said the war had killed 5,000 Hezbollah fighters and wounded 13,000, the first official toll the group has given. But he said the organisation remained in good order, with fighters ready to make "the harshest sacrifices" if needed.

Minutes after he spoke, dozens of men on motorcycles carrying Hezbollah's yellow flags emerged from its strongholds in Beirut's southern suburbs for the second day in a row.

Rejects 'external dictates'

Washington and Beirut have been in talks since June on a U.S. roadmap to fully disarm Hezbollah in exchange for a halt to Israeli strikes, the withdrawal of Israeli troops still occupying five points in south Lebanon and funds to rebuild areas destroyed by Israeli bombardment during the war.

But with little progress on disarmament, Washington's patience began wearing thin and it pressured Lebanon's ministers to swiftly make a public pledge so that talks could continue.

Qassem pushed back against the conditions, saying Israel must implement the ceasefire in full by halting its military activities in Lebanon before any other discussion.

"Solve the problem of the (Israeli) aggression, and then we will discuss the issue of the weapons," he said.

Addressing Lebanese officials, he said: "I hope you don't waste time on the storms stirred up by external dictates."