Israel has imposed a last-minute curfew forbidding any Lebanese from crossing into the south of the country.
Starting in the early hours of this morning, Israel and Hezbollah agreed to a 60-day pause halting a conflict that has killed thousands in Lebanon and displaced many more.
At 2.30pm UK time (4.30pm locally), Israel's Arab spokesperson warned movement south of the Litani River in Lebanon is "absolutely forbidden" - starting in half an hour.
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"Whoever is north of the Litani River is prohibited from moving south. Whoever is south of the Litani River must remain where he is," the statement added.
"We remind you that the IDF is still deployed in its positions in southern Lebanon in accordance with the terms of the ceasefire agreement, and our forces will deal firmly with any movement that violates this agreement."
The ceasefire deal, published by Lebanon's cabinet, marks an area delineated by a red line labelled "New 2024 line" running east-west across the country.
This area - mostly along the Litani River before diverging slightly north and covering the south of the country - must remain free of Hezbollah weapons, according to the deal.
The terms stipulate only "official military and security forces" in Lebanon are authorised to carry arms, with the foreign minister saying it could deploy at least 5,000 troops.
If Israel believes Hezbollah has violated the terms, Prime Minister Benjamin Netanyahu said they have the right to attack, though Lebanese and Hezbollah officials reportedly claim otherwise.
The deal expects Hezbollah forces to leave their positions in southern Lebanon and retreat north of the Litani River, US President Joe Biden said.
Israel will withdraw its forces from Lebanon over a period of 60 days, he added, as the Lebanese army takes control of the area to ensure Hezbollah does not rebuild there.
Around an hour after the truce started, Reuters reported streams of cars were already heading to south Lebanon.
Within Israel, there was significant opposition to the ceasefire, with a poll conducted by Israel's Channel 12 TV station finding 37% were in favour of the ceasefire and 32% against.
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In Lebanon, people cheered on the streets as the truce was confirmed.
Gunfire was also heard in the early hours of Wednesday morning in Beirut after the ceasefire began - it was not clear if it was celebratory.
On Wednesday morning, IDF spokesperson Avichay Adraee had urged people not to return to their homes in south Lebanon, saying Israeli forces were still deployed there.
He claimed they were "prohibited" from going back to areas the IDF had asked people to evacuate previously.
The ceasefire will be monitored by an international panel led by the US, along with thousands of Lebanese troops and UN peacekeepers deployed around the border.
(c) Sky News 2024: Israel imposes curfew in Lebanon at last minute as Hezbollah ceasefire begins