"Our collective responsibility in the region is to work toward preventing an American war on Iran," Sayyed Hassan Nasrallah said during a televised interview with Hezbollah’s Al-Manar television on Friday, AFP reported.
Nasrallah said that neither Saudi Arabia nor the United Arab Emirates (UAE) had any interest in conflict.
He also warned that US ally Israel would not be "neutral" if a war broke out between the United States and Iran.
"Iran is able to bombard Israel with ferocity and force," Nasrallah said.
His remarks came after weeks of increasing tensions between the United States and Iran, and as US President Donald Trump steps up his war of words with the Islamic Republic.
"When the Americans understand that this war could wipe out Israel, they will reconsider," Nasrallah said.
The United States has blacklisted Hezbollah, which is a major political player in the small Mediterranean country, taking 13 seats in Parliament last year and securing three posts in the current cabinet.
Tel Aviv 'within range'
Responding to a question about repeated Israeli airstrikes on Syria, Nasrallah said the Israeli Prime Minister Benjamin Netanyahu was "deceiving his people."
"He is playing a game of brinkmanship, because Iran will not leave Syria," he warned.
Israel has carried out hundreds of strikes in neighboring Syria against what it says are Iranian and Hezbollah military targets. It has vowed to keep Iran from entrenching itself militarily there.
Nasrallah's interview came to mark the start of his movement's 2006 war with Israel, which killed more than 1,200 Lebanese, mostly civilians, and more than 160 Israelis, mostly soldiers.
Both Israel and Lebanon are still technically at war.
Nasrallah warned that key Israeli installations along the Mediterranean coast including Tel Aviv were "within range of our rockets."
Syria presence downgraded
Nasrallah also said he had decreased the number of his movement's fighters supporting the government in neighboring war-torn Syria.
"The Syrian Army has greatly recovered and has found that today it does not need us," he said.
"We are present in every area that we used to be. We are still there, but we don't need to be there in large numbers as long as there is no practical need," he said.
The head of the Iran-backed Shia movement, which has been present in Syria since 2013, did not give details on the extent of the reduction.
But "if there was a need to return, all those who were there would go back" to Syria, he added.
Backed by Russia and Iran, the Damascus government has taken back large swathes of territory from terrorists since 2015, and now controls around 60 percent of the country.
Nasrallah spoke after Washington announced fresh sanctions Tuesday against Hezbollah, targeting elected officials from the movement for the first time.