The warning on Wednesday came after the military launched what it said were limited ground operations near the border to combat the Hezbollah militant group.
The villages are in a UN-declared buffer zone established after Israel and Hezbollah fought their last war in 2006.
Already battling Hamas in Gaza, Israel is beefing up its presence in south Lebanon a day after it was attacked by Iran, raising fears the oil-producing Middle East could be engulfed in a wider conflict.
Israel is increasing its military presence in southern Lebanon after launching raids there. (AP PHOTO)
The addition of infantry and armoured troops from the 36th Division, including the Golani Brigade, the 188th Armoured Brigade and 6th Infantry Brigade, suggests the operation has moved beyond limited commando raids.
The military has said the ground operation is largely aimed at destroying tunnels and other infrastructure on the border and there were no plans for a wider operation targeting Beirut or major cities in southern Lebanon.
Iran said on Wednesday its missile attack on Israel - its biggest military assault on the country - was over barring further provocation, while Israel and the United States promised to hit back.
Israel will launch a "significant retaliation" within days that could target oil production facilities inside Iran and other strategic sites, US news website Axios reported on Wednesday, citing Israeli officials.
Despite calls for a ceasefire from the United Nations, the United States and the European Union, fighting between Israel and the Lebanon-based Hezbollah continued on Wednesday.
Israeli authorities estimate more than 180 ballistic missiles were fired by Iran's forces. (AP PHOTO)
Israel renewed its bombardment of Beirut's southern suburbs with at least a dozen airstrikes against what it said were targets belonging to Hezbollah.
Large plumes of smoke were seen rising from parts of the suburbs. Israel issued new evacuation orders for the area, which has largely emptied after days of heavy strikes.
Hezbollah said it confronted Israeli forces infiltrating the Lebanese town of Adaisseh early on Wednesday and forced them to retreat.
Iran said Tuesday's assault on Israel was solely aimed at military facilities. Iran's state news agency said three Israeli military bases had been targeted.
Tehran said its assault was a response to Israeli killings of militant leaders and aggression in Lebanon against Hezbollah and in Gaza.
"Our action is concluded unless the Israeli regime decides to invite further retaliation. In that scenario, our response will be stronger and more powerful," Iranian Foreign Minister Abbas Araqchi said in a post on social media platform X early on Wednesday.
Earlier this evening, we exercised self-defense under Article 51 of the UN Charter, targeting solely military & security sites in charge of genocide in — Seyed Abbas Araghchi (@araghchi) #Gaza and #Lebanon. We did so after exercising tremendous restraint for almost two months, to give space for a ceasefire in… pic.twitter.com/SJJrAhxIdNOctober 1, 2024
Israeli Prime Minister Benjamin Netanyahu has vowed to strike back.
"Iran made a big mistake tonight - and it will pay for it," he said at the outset of an emergency political security cabinet meeting late on Tuesday, according to a statement.
Washington said it would work with longtime ally Israel to ensure Iran faced "severe consequences" for Tuesday's attack, which Israel said involved more than 180 ballistic missiles.
US Secretary of Defence Lloyd Austin spoke to Israeli Defence Minister Yoav Gallant late on Tuesday and said Washington was "well-postured" to defend its interests in the Middle East, the Pentagon said in a statement.
US Navy warships fired about a dozen interceptors against Iranian missiles headed toward Israel, the Pentagon said.
Britain said its forces played a part "in attempts to prevent further escalation in the Middle East", without elaborating.
The Pentagon said Tuesday's airstrikes by Iran were about twice the size of April's assault by Iran on Israel.
German Chancellor Olaf Scholz called on Iran and Hezbollah to immediately end their attacks on Israel and warned that Iran risks inflaming the entire region.
Japan said it is deeply concerned by the situation.
With AP
