Nasrallah told the Hezbollah's al-Manar news channel that a strong deterrent was needed in the face of Israeli aggression.
"When Israel threatens to destroy Lebanon, it is our duty to stand in its face and say: This era is over," he said.
Hezbollah and Israel went to war briefly in 2006. A U.N. Security Council resolution that helped broker a cease-fire calls on Hezbollah to disarm while reminding Israel of its obligations to respect Lebanese sovereignty.
Nasrallah last month said "the No. 1 threat for Israel" in the world is Hezbollah.
"If Israel attacks us, all options are open," he said during the interview.
He maintained, however, that there were no chemical weapons in Hezbollah's arsenal.
The U.S. Departments of Treasury and State in August sanctioned Hezbollah for backing the Syrian regime, under pressure for the international community for fighting in the country.
Hezbollah is listed as a terrorist organization by the U.S. government.
The movement's Deputy Secretary-General Naim Qassem had said his group opposed foreign interference in the conflict.