In early October, the Israeli military began ground operations in southern Lebanon; Israel described its ground operations as "limited" and said they were aimed at "destroying Hezbollah's capabilities."

There was local fear that this Israeli invasion would turn into a long-term “occupation” – although Israel has repeatedly indirectly denied its intention to do so.

The Israeli army had previously invaded southern Lebanon in "Operation Litani" in 1978, and then in 1982 in an operation known locally as the "1982 Lebanon War" or "1982 Lebanon Invasion", while Israel calls it the "First Lebanon War" - at that time the Israeli army reached the capital Beirut by land.

In 1985, most of his forces withdrew, but he remained present in areas in southern Lebanon until 2000, and he extended his authority through what was called the "South Lebanon Army" or "Lahad Militia", which was affiliated with him. Israel also carried out a limited ground invasion in 2006.

How does international law view the current Israeli ground incursion into Lebanese territory?

The answer may not be easy or straightforward; interpretations of the law vary, especially because there are gaps and terms left unexplained.

The Israeli ground incursion comes after more than a year of mutual shelling between Israel and Hezbollah across the Lebanese-Israeli border, which has displaced hundreds of thousands of civilians on both sides.

Israel is demanding that residents of villages in southern Lebanon "immediately evacuate their homes and move immediately to the north of the Awali River," which separates southern Lebanon from the Chouf region in Mount Lebanon Governorate.

The Israeli army spokesman for the Arab media, Avichay Adraee, says in his instructions, which he publishes on the X platform, that “any movement towards the south could pose a danger to your lives” and that the Israeli army will inform the southerners “at the appropriate time to return to your homes when the appropriate conditions are available for that.”

Although Israel has been violating Lebanese airspace even before the latest round of fighting, the ground operations appear to be raising concerns among the Lebanese.

According to legal experts, Hezbollah's continued military presence south of the Litani River is a violation of Resolution 1701, which was unanimously adopted by the UN Security Council in August 2006 and ended the 34-day war between Israel and Hezbollah.

Dr. Karim El Mufti, Professor of International Relations and International Law at the Institute of Political Studies in Paris, answered the question in a phone call with BBC Arabic by saying that any operation carried out by a foreign army in another country, by land, sea or air, is considered in international law to be a “hostile act” or “aggression,” and in all its forms constitutes a breach of the sovereignty of the targeted country and a violation of the United Nations Charter.

Regarding Israel's entry into Lebanese territory, the Mufti says that this "also constitutes a violation of international resolutions such as Resolution 425 in 1978 and Resolution 1701."

Resolution 425, issued by the Security Council in 1978, calls for the immediate withdrawal of Israeli forces from Lebanese territory and respect for Lebanon’s sovereignty and internationally recognized borders. The resolution also responded to Lebanon’s call to establish a United Nations Interim Force in Lebanon (UNIFIL) under the Council’s supervision.

Regarding the difference between the descriptions of “ground operation,” “invasion,” and “invasion,” Professor Christian Henderson, a lecturer in international law at the University of Sussex in Britain, told us that international law has not clearly defined invasion, invasion, or ground operation, and therefore, there is no legal difference between them.

"But it can be said that a ground incursion may be more related to a limited border dispute, while an invasion is deeper than that, in the middle of a land and not just on its edges," he adds.

He continues: "While the ground operation does not provide more information than that there are soldiers on the ground."

Henderson says the difference in the use of these names between the conflicting countries is due to political, not legal, reasons.

He gives an example from Ukraine: “Russia says it is conducting a special military operation there, and it does not describe what it is doing as a war. There is no legal meaning to that, but it has a political meaning.”

Because international law does not contain a definition for every military action, each party chooses a specific term and definition that serves its narrative, as Professor of International Law Al-Mufti says. “Each party uses the law - national or international - in a way that serves its interests.”

Leila Nicola, a professor of international relations at the Lebanese University, also agrees with this point. She tells BBC Arabic, “States usually formulate different names for their invasion of another state’s territory to evade the legal responsibility resulting from this matter, and because violating the sovereignty of another state through invasion or occupation is prohibited by international law.”

Nicola gives an example of this by saying that Israel used the word “ground operation” in southern Lebanon instead of “ground invasion” or “invasion.”

But for Henderson, things are more complicated than that.

"It's more complicated than that."

He explains his view by saying: “Israel argues that it is acting in self-defense in both Gaza and Lebanon after attacks on it.”

He added that "states have the right to carry out military operations within the land or air borders of another state, if armed attacks are launched from there that threaten its security, even if the person responsible for these attacks is a non-governmental armed group."

He explains this point, saying: “These groups ultimately operate from within the borders of another state, even if that state is completely neutral with regard to this conflict. These states are usually either unable to stop this armed group, or simply unwilling to do so.”

But he adds that the basic thing in the response of the state attacked by the armed group is that whatever they do must be “necessary” and subject to the principle of “proportionality.”

He continues: “These two expressions are fundamental in international law, but they are not defined in a clear and unambiguous manner.”

"If it appears that what they are doing is motivated by revenge or punishment, then of course we cannot talk about self-defense here," Henderson points out.

"The goal should be only deterrence and self-defense," he continues.

Henderson believes that Israel's goal of "totally destroying Hezbollah" is "totally disproportionate to the motive of self-defense" because "Hezbollah is not only an armed group, but also has a political arm and an arm responsible for providing humanitarian and social assistance to some segments of Lebanese society," he believes.

Hezbollah participates in the Lebanese parliament and government, and has a scout, an ambulance, and a social financial association.

Where does the siege and occupation begin?

Israel bombed the international roads that lead between Lebanon and Syria - the most important of which is the Masnaa crossing - and issued orders to evacuate the land areas and sea areas adjacent to the Mediterranean coast from the Awali River to southern Lebanon.

Israeli army spokesman Daniel Hagari also warned in late September that his country's army would prevent "the transfer of weapons to Hezbollah through Beirut International Airport."

There is no definition of “siege” or “encirclement” in international humanitarian law, but the International Committee of the Red Cross defines a siege as “a tactic of encircling enemy armed forces in order to prevent their movement or to cut off their channels of support and supply.”

Nicola believes that “the siege may be declared and clear, or it may be implicit.”

In her opinion, "what Israel is doing in terms of cutting off land communication with Syria, controlling sea and air ports, and threatening to use force against any violation, means that Israel is imposing a siege on Lebanon, even if it does not announce it publicly, because it is a violation of international law, and because it could be subject to international and global condemnation if it is disclosed clearly and directly."

Israeli Prime Minister Benjamin Netanyahu said in more than one video clip addressing the Lebanese that "Israel's war is not with the Lebanese" but rather "against Hezbollah."

Israel says that through its war it seeks to "undermine Hezbollah's capabilities," while Lebanese officials argue that the raids "target unarmed civilians."

Caretaker Prime Minister Najib Mikati said, "A ceasefire and an end to the bombing of civilians are our basic demands."

Karim Al-Mufti told BBC Arabic that the blockade may occur in certain areas within Lebanon even if it does not occur to all of Lebanon.

The Mufti refers to the July 2006 war, “when the Israeli army besieged the southern town of Rmeish and prevented the International Red Cross from bringing in aid. All the people of the neighboring towns had fled to Rmeish, thinking it was safer.”

He added: "The siege was lifted after days of diplomatic, humanitarian and political pressure."

With regard to occupation, international humanitarian law defines occupation as “the effective control and domination of a territory by a hostile army.”

Laila Nicola explains: “When a state exercises actual control over the territory of another state, it is called an occupying state, and in law it does not acquire sovereignty over it, no matter how long the occupation lasts.”

She added: "After a country occupies this piece of land, it becomes obligated to treat the population humanely. International humanitarian law prohibits the displacement of the population, uprooting them from their land, or carrying out killings or enforced disappearances. It also prohibits settlement operations, and requires the occupying state to provide them with basic needs."

The Mufti also considers that the definition of occupation is not entirely clear, but it becomes “clear” with evidence of actual control of the land in which the foreign army is located.

The Mufti cites the incident of a prison in the town of Khiam in southern Lebanon that was controlled by the militia that was carrying out Israel's orders in 1982, as legal evidence that "Israel was practicing the act of occupation" at that time.

The force assigned to guard the prison withdrew on May 23, 2000, and the residents stormed the prison and freed the detainees, who were estimated to number more than 140.

Lebanon celebrates the withdrawal of the Israeli army from the south of the country on May 25 of each year.