Israeli troops seize castle in deepest incursion into Lebanon in 26 years

Israeli troops have seized the 900-year-old Beaufort castle in southern Lebanon. (Supplied: X/Avichay Adraee)

The Israeli military says it has captured Beaufort castle and its strategic ridge in southern Lebanon, after days of intense fighting and air strikes in nearby villages.

The capture is a major advance against Iran-backed Hezbollah, despite a ceasefire announced more than six weeks ago.

The next round of talks on an Israel-Lebanon ceasefire is set to be held in Washington on June 2 and 3.

Israeli troops have captured a strategic mountain topped with a Crusader-built castle in southern Lebanon in their deepest incursion into the country in 26 years, the military says.

The capture of Beaufort castle near the city of Nabatiyeh came after days of intense fighting and air strikes in nearby villages where Israeli troops fought Hezbollah members in the rugged area.

It marks a major gain for Israel in the latest Israel-Hezbollah war, which began in early March.

Israel and Lebanon have been at war since Israel was created in 1948, and are currently holding direct talks in Washington.

The Israeli push came despite a nominal ceasefire that has been in place since April 17 and just days before the next round of talks are set to be held at the US State Department on June 2 and 3.

The Israeli army's Arabic spokesperson, Avichay Adraee, posted a photo on X showing Israeli troops walking outside the castle, and Defense Minister Israel Katz wrote on X that they had raised an Israeli flag over the castle.

The Israeli capture of the castle and strategic ridge is a major advance against Iran-backed Hezbollah. (Supplied: X/Avichay Adraee)

Israeli troops previously captured the castle in 1982 and held it until they withdrew from Lebanon in 2000.

The advance has granted Israeli troops an overlook point over much of southern Lebanon and northern Israel, from which attacks have been launched towards Israeli residential areas.

The Israeli military said in a statement that it launched an operation a few days ago in the Beaufort Ridge and the Suluki valley further south with the aim of dismantling Hezbollah infrastructure and removing "direct threats to Israeli civilians".

The statement said the army is ready "to expand the operation if needed".

In recent days, Israel has expanded the scope of its operations in Lebanon, sending troops across the Litani River, which previously served as a de facto boundary, and demanding that residents leave much of southern Lebanon.

New waves of missile strikes and vast advisories from the Israeli government to evacuate have