Minutes before the ceasefire came into effect at midnight, a series of Israeli strikes in the southern city of Tyre killed at least 13 people and destroyed six residential buildings, a city official said.

Under the terms of the truce, Israel reserves the right to continue targeting Hezbollah to prevent "planned, imminent, or ongoing attacks", and it says it will maintain a 10-kilometre (six-mile) security zone along the border in southern Lebanon.

According to details of the truce deal released by the US State Department, Lebanon "with international support... will take meaningful steps to prevent Hezbollah" from undertaking any attacks or hostile actions against Israeli targets.

The Iran-backed movement, meanwhile, said its finger remains "on the trigger" in the event of any violations.

Despite warnings against returning to the south, long queues of displaced families began traversing the bomb-damaged Qasmiyeh bridge near the southern city of Tyre on Friday after bulldozers restored the crossing so they could head home, according to AFP journalists.

For some returnees, the short truce between Israel and the Lebanese government, brokered under pressure from US President Donald Trump, was a new source of hope.

"Our feelings are indescribable, pride and victory," 37-year-old Amani Atrash told AFP from her car seat, adding she hoped the truce would be extended.

Across the border in Israel, the military's home front command had not yet removed restrictions on civilian movements in vulnerable border areas.

Still, some civilians there were daring to hope for a return to a more normal life.

"I've got a three-year-old girl and a two-month-old baby, and the whole time we've just not left the house because you never know when there'll be a rocket attack," 31-year-old Ofir Ben-Ari told AFP.

"It's been crazy, but I think things will be quiet now and I'll be able to take my daughter to the park", she added.

- 'High alert' -

Iran-backed Hezbollah, which has been pummelled by Israeli strikes and engaged its forces on the ground in the south, has indicated it will respect the truce unless Lebanon is attacked again.

"The fighters will keep their finger on the trigger because they are wary of the enemy's treachery," the movement said in a statement.

The ceasefire represents a key step in Washington's efforts to reach a deal to end its war with Iran, after Tehran insisted that halting the Lebanon fighting must be part of any agreement.

Pakistan has been leading a diplomatic push to restart face-to-face talks between Tehran and Washington, and Trump said they were "very close" to striking an agreement.

The fighting broke out in Lebanon on March 2 when Hezbollah fired rockets at Israel a few days after the start of the Middle East war in retribution for the killing of Iran's supreme leader Ali Khamenei.

As the ceasefire came into effect, Israel's military said it had struck over 380 "Hezbollah terror organisation targets in southern Lebanon" and was on "high alert" to resume strikes.

Trump said he had spoken to both Israeli Prime Minister Benjamin Netanyahu and Lebanese President Joseph Aoun ahead of the truce, which he said they had agreed "in order to achieve PEACE between their Countries".

He later said he expected Netanyahu and Aoun to visit the White House in the coming days.

- 'Very happy' -

A top-level face-to-face meeting between the Lebanese and Israeli leadership would be a watershed moment for the region. But it remained to be seen whether it would take place.

Netanyahu said the ceasefire with Lebanon offered an opportunity for a "historic peace agreement" with Beirut -- but insisted that the disarmament of Hezbollah remained a precondition.

Lebanese Prime Minister Nawaf Salam welcomed Trump's announcement, saying a truce was a "key Lebanese demand that we have pursued since the very first day of the war".

But the Lebanese president had rejected Trump's request for a direct call with Netanyahu, an official source told AFP.

Trump called the developments "very exciting", in response to a question from an AFP reporter as he left the White House.

"Today they're going to be having a ceasefire, and that'll include Hezbollah," he said.

Hezbollah lawmaker Ibrahim al-Moussawi told AFP it would "cautiously adhere" to the truce if Israeli attacks stopped, thanking Iran for having applied pressure in Lebanon's favour.

Iranian state television portrayed the ceasefire as the result, in part, of Tehran's "insistence".

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