Elias Murr, the Lebanese defence minister, rejected the Hezbollah demand, saying the weapons would be handed over to the under-equipped Lebanese army.
The truck had been carrying the load from the Bekaa Valley in the east to the south, the Shia group said in a statement.
Ghazi Aridi, the Lebanese information minister, said earlier that the authorities had stopped a truck carrying weapons on the edge of Beirut and took it away for investigation.
Hezbollah's statement said: "The government programme clearly confirms the right of the resistance ... to work to liberate the rest of the occupied land, the prisoners and to confront the Zionist threats."
The Lebanese and Israeli armies clashed on the border on Wednesday, causing no casualties but with the UN warning of the possibility of escalation.
Murr told Lebanon's private LBC television channel: "I would have liked for Hezbollah to donate its weapons to the Lebanese army which last night managed to repel Israeli aggression against Lebanese territory."
UN resolution
Hezbollah fought with Israeli forces during last summer's conflict which left at least 1,200 Lebanese - mostly civilians, and 157 Israelis - mostly soldiers, dead.
The conflict ended following a UN Security Council resolution which authorised the deployment of thousands of UN troops to monitor a truce between the warring parties.
Under the resolution the Lebanese government is supposed to halt the flow of weapons to Hezbollah from abroad .
A UN envoy and anti-Syrian Lebanese leaders have accused Syria of smuggling weapons to its allies in Lebanon in recent months.
Israeli occupation
Hezbollah is part of the opposition movement which has organised protests and strikes demanding veto power in government and fresh elections.
The political standoff spilled over into armed clashes last month and nine people were killed.
Hezbollah was the only armed group which was not asked to surrender its weapons after the country's 1975-1990 civil war because it was considered a "resistance group" then fighting Israel's occupation of Lebanese territory.
It says it needs the arms partly because of Israel's continued occupation of Shebaa Farms - territory occupied since the 1967 Middle East war.
The Shebaa Farms are claimed by Lebanon, while the UN says they belong to Syria.
Damascus says the land belongs to Lebanon.