The heads of the Pakistani and Lebanese armed forces agreed to boost cooperation on Tuesday as they met in Pakistan with peace talks over the Middle East war dragging on.

Pakistan has been mediating between the United States and Iran to end the months-long conflict, with Tehran insisting that any deal should include Lebanon.

Israeli Defense Minister Israel Katz has vowed to press on with Israel's military campaign in Lebanon, despite a warning from Iran that any such action would prompt the Islamic republic to take "severe" measures in response.

"The IDF will continue to operate in Lebanon against the terrorist organization Hezbollah," Katz said in a statement Monday, adding that Israel would strike Beirut's southern suburbs, known as Dahieh, in retaliation for every attack on northern Israel.

The Israeli army ordered Tuesday residents of the historic city of Tyre and its suburbs, including the city's Christian neighborhood, to evacuate ahead of expected strikes.

"Urgent warning to the residents of the city of Tyre, including the Christian quarter, and the camps and surrounding neighborhoods," read a message posted on X by the Israeli military's Arabic-language spokesman Avichay Adraee.

Iranian President Masoud Pezeshkian on Monday said Tehran remained at the negotiating table after halting attacks on Israel following the first exchange of fire since the April truce.

"Diplomacy and defense are the two wings of national power; we have neither left the battlefield nor the negotiating table," Pezeshkian said in a post on X, adding that Tehran "will not retreat in the face of any threat".

A senior Hezbollah official told AFP on Monday that the Iran-backed group has had "no direct contact" with President Donald Trump, despite recent statements from the US leader suggesting otherwise.

Washington considers Hezbollah a "terrorist" group, including both its military and political wings, and recently imposed sanctions on several of its lawmakers.

Lebanese Culture Minister Ghassan Salame on Monday appealed for historic sites to be spared as AFP correspondents saw damage to a World Heritage site in south Lebanon's Tyre after Israeli bombardment.

One of the oldest cities on the Mediterranean coast, Tyre lies around 20 kilometers from the Israeli border, and its UNESCO World Heritage-listed ruins are located in two main areas of the city.

Local media in Iran said Monday that a "hostile drone" was shot down over the capital Tehran during the new round of fighting with Israel.

"A hostile drone belonging to the American-Zionist enemy was targeted and destroyed by air defenses in the skies over Tehran," the Mehr news agency reported, without elaborating.

The Israeli military said Monday it had struck and dismantled Iranian defense systems deployed across several areas in the country.

"Recently, defense systems were deployed in numerous areas across Iran as part of the regime's efforts to restore its detection and defense capabilities, which were degraded during Operation Roaring Lion," the military said.

Iran said Monday that the United States held responsibility for the resumption of fighting with Israel, saying Israel's actions "cannot be separated" from U.S. policy.

"Without a doubt, as I said, the actions of the Zionist regime in the region cannot be separated from U.S. policies," foreign ministry spokesman Esmaeil Baqaei said at a press conference in Tehran attended by AFP.

The Israeli military has vowed to press ahead with its military campaign in Lebanon and said it would step up operations against Hezbollah.

"The (Iranian) regime is attempting to establish a new equation through direct attacks on Israeli territory in response to IDF operations in Dahieh," military spokesman Brigadier General Effie Defrin said Sunday, in a televised statement.