Lebanon's Defense Minister offered advice on how Israel could defeat Hezbollah if a new war erupted on Israel's northern border, a classified U.S. diplomatic cable shows.

In a future replay of its 2006 invasion of southern Lebanon, Israel should take care not to antagonize local Christian communities, Elias Murr told the United States embassy in Beirut, according to a document released by the WikiLeaks group.

"Israel cannot bomb bridges and infrastructure in the Christian areas," Murr was quoted as saying in the cable, sent by a U.S. diplomat to the State Department in Washington. "The Christians were supporting Israel in 2006 until they started bombing their bridges."

Israel fought a month-long war with Hezbollah militants in the summer of 2006, sending ground troops into southern Lebanon and bombing infrastructure targets as far north as Beirut.

In the run-up to an invasion, the Israel Defense Forces should also take care not to enter a United Nations-controlled buffer zone along the border, Murr said. He said Hezbollah would use any Israeli violation of UN Security Council 1701, which brought an end to the 2006 war, to "flood" the area with fighters and weapons.

Murr also told the diplomat that Hezbollah, despite claiming victory in 2006, when it inflicted heavy IDF casualties, was far less confident of holding off another Israeli attack.

"I am sure Hezbollah is scared and they are preparing for a severe lesson this time," he was quoted as saying.

He said Hezbollah felt it had no choice but to respond to the assassination of Imad Mughniyeh, a militant commander killed in Damascus in 2008. Hezbollah has accused Israel of the attack.

"Murr thinks that an attack in West Africa or South America would be easier for Hezbollah but he thinks [the goup's spiritual leader Hassan] Nasrallah would prefer to attack inside of Israel if possible," Murr said. "Hezbollah will attempt to bring in Syria to absorb some of the Israeli response to their attack."

While Israel and Lebanon each classify the other as a hostile nation, Murr said that if war broke out, his main concern would be to keep the Lebanese Army out of the fighting.

"Murr was especially concerned for members of the 1st and 8th Brigades in the Beka'a valley. Murr thinks that these units will be cut off from HQ support while Israel is conducting operations against Hezbollah," the diplomat reported.

"They will have to turn to the local populace for food, water etc. Since the populace is mainly Hizballah supporters, Murr is afraid that these two units could be dragged into the fight, the ultimate disaster Murr hopes to avoid."

Later in the meeting, Murr sought information on how long invading Israeli troops might take to "clean out" Hezbollah so that supplies could be stored for Lebanese units operating in Hezbollah-controlled areas.

The defense minister also said he had told the army's commander at the time, Michel Sleiman – currently Lebanon's president – to keep out of the fighting "when Israel comes".

"Murr's opinion is that an Israeli action against Hizballah would not be a war against Lebanon and that Syria and Iran did not ask Lebanon's permission to equip Hezballah with its rockets," the report said.

"As such, the Lebanese Army has been ordered to not get involved with any fighting."

For Murr, the army's strategic objective was to survive a three week war "completely intact" and able to take over once Hizballah's militia has been destroyed, the report said.

"I do not want thousands of our soldiers to die for no reason," Murr was quoted as saying.