BEIRUT, Oct 11 (Mariam Karouny/Reuters) - Lebanese Hezbollah leader Sayyed Hassan Nasrallah acknowledged on Thursday sending a drone aircraft that was shot down last weekend after flying some 25 miles (55 km) into Israel.

Nasrallah said in a televised speech that the drone's parts were manufactured in Iran and it was assembled by members of the Shi'ite Muslim militant movement in Lebanon. He confirmed a statement by Israel's prime minister earlier in the day saying that Hezbollah was behind the drone flight.

The resistance in Lebanon sent a sophisticated reconnaissance aircraft from Lebanon...It penetrated the enemy's iron procedures and entered occupied southern Palestine, Nasrallah said. Hezbollah does not recognize the state of Israel.

Tensions have increased in the region with Israel threatening to bomb the nuclear sites of Hezbollah's patron Iran if diplomacy and sanctions fail to stop Iranian nuclear activity the West suspects is meant to develop a weapons capability. Tehran says it is seeking only civilian nuclear energy.

Iran has threatened in turn to attack U.S. military bases in the Middle East and retaliate against Israel if attacked.

Seeking to underline that Hezbollah was capable of reaching targets well inside Israel, Nasrallah said the drone flew over sensitive installations inside southern Palestine and was shot down in an area near the Dimona nuclear reactor.

Iran said the incursion exposed the weakness of Israeli air defense, indicating that Israel's Iron Dome anti-missile defense system does not work and lacks the necessary capacity. The Iron Dome system, jointly funded with Washington, is designed to down short-range guerrilla rockets, not slow-flying aircraft.

Hezbollah last fought Israel in 2006 during a 34-day war in which 1,200 people in Lebanon, mostly civilians, and 160 Israelis, mostly soldiers, were killed.

Since that war, Hezbollah has a number of times suggested it had expanded its arsenal in an apparent strategy of deterrence.

Hezbollah is also an ally of Syrian President Bashar al-Assad, who is fighting to put down a 19-month-old uprising that has turned into a civil war with sectarian dimensions, largely pitting the majority Sunni Muslims against Assad's minority Alawite community, who are an offshoot of Shi'ite Islam.

Nasrallah has explicitly expressed political support for Assad, whose opponents have accused Hezbollah of sending fighters to help the Syrian leader quell the insurgency.

Nasrallah denied such accusations. We have not fought alongside the regime until now. The regime did not ask us to do so and also who says that doing so is in Lebanon's interest?

Earlier this month Hezbollah buried two of its fighters who local sources said were killed near a Syrian border town. Hezbollah acknowledged the death of only one fighter and said he was a commander who died while performing his jihad duties. It did not elaborate. Nasrallah said on Thursday that he was killed in a roadside bomb in a town near the Syrian border.

Last month, the U.S. Treasury imposed sanctions on Nasrallah for what it said was support given to Assad against anti-government protests, as well as two other members for the group's terrorist activities in general.