Hezbollah chief Naim Qassem. File Photo
Qassem spoke in a televised address after meeting Iran's top security chief Ali Larijani, whose country has long backed the Lebanese Shia group.
Beirut's disarmament push followed a deadly Israeli war against Lebanon that saw Israel escalate indiscriminate strikes, mainly in the south, where Hezbollah supporters are concentrated.
The Israeli aggression has significantly affected Hezbollah, which has traditionally guarded Lebanon’s southern borders against Israeli incursions.
Iran, whose so-called "axis of resistance" includes Hezbollah, has also been impacted by Israeli aggression, most recently in the war with Israel, during which the United States struck its nuclear sites.
"The government is implementing an American-Israeli order to end the resistance, even if it leads to civil war and internal strife," Qassem said.
"The resistance will not surrender its weapons while aggression continues, occupation persists, and we will fight it... if necessary to confront this American-Israeli project no matter the cost," he said.
Qassem urged the government "not to hand over the country to an insatiable Israeli aggressor or an American tyrant with limitless greed".
He also said the government would "bear responsibility for any internal explosion and any destruction of Lebanon", accusing it of "leading the country to ruin".
Hezbollah and its ally Amal would not be organising any street protests at this time, he said, while threatening to do so in future.
The Lebanese government has cast disarmament as part of the implementation of the November ceasefire that sought to end Israel's escalation against Lebanon.
Under the truce, Hezbollah was to withdraw north of Lebanon’s Litani River and dismantle any remaining military infrastructure in the south, while Israel was to pull all its forces from southern Lebanon.
However, Israel has continued to occupy five key areas in the south, in clear violation of the truce terms.
Lebanon says it has respected its ceasefire commitments and has called on the international community to pressure Israel to end its attacks and withdraw all its troops.
Hezbollah has complied with disarmament requirements in southern Lebanon but has refused to disarm in other parts of the country, arguing that the state cannot claim sole authority over weapons until Israel fully withdraws from Lebanese territory.
The group was founded in 1982 in response to Israel’s second invasion and occupation of Lebanon that year. Israel’s first invasion was in 1978, several years before Hezbollah was established.
Hezbollah was the only faction allowed to retain its weapons after Lebanon’s civil war ended in 1990.
The group has long maintained that it must keep its arsenal to defend Lebanon from attack.
Iran's Supreme National Security Council chief Larijani was in Beirut this week, where he met Qassem as well as with President Joseph Aoun.
Iran has expressed its opposition to the government's disarmament plan, and has vowed to continue to provide support.
Aoun told Larijani that he rejected any interference in the country's internal affairs, branding as "unconstructive" Iran's statements on plans to disarm Hezbollah.
*This story was edited by Ahram Online.
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