BEIRUT - Hezbollah's leader Naim Qassem said on Saturday the ceasefire with Israel must mean a complete halt to aggression, warning the group will retaliate against Israeli violations in southern Lebanon.

"There is no ceasefire from one side only," Qassem said in a statement, adding that Hezbollah fighters "will respond to violations of aggression accordingly."

He outlined five key steps: a permanent halt to hostilities across Lebanon, a full Israeli withdrawal, detainee releases, the return of displaced residents, and reconstruction with Arab and international support.

Hezbollah had not been defeated and would continue to pursue Lebanon's liberation and independence, he added.

Qassem also said Hezbollah is open to "a new page" of cooperation with the Lebanese government, stressing readiness to work with state institutions to strengthen national unity and safeguard sovereignty.

A 10-day ceasefire between Israel and Lebanon took effect at midnight between Thursday and Friday local time (2100 GMT), following an earlier announcement by U.S. President Donald Trump.

However, the Israel Defense Forces said in a statement on Saturday that it had struck militants approaching a "Yellow Line," which marks the northern edge of the "security zone" established by Israel in southern Lebanon, over the past day.

The Israeli army also began constructing a new military site on Saturday near Kfarchouba village in the eastern sector of southern Lebanon's border area, according to eyewitnesses and a Lebanese security source.

The Lebanese security source told Xinhua that an Israeli military unit, comprising bulldozers and excavators, and protected by a Merkava tank, was conducting earthmoving works on a hill southwest of Kfarchouba. Activities included ground leveling, excavations, and the construction of earth berms, indicating the establishment of a new military post administratively linked to Kfarchouba.

Eyewitnesses identified the site as "Rbaa al-Teben" hill, about 1.5 km from the Lebanon-Israel demarcation line and home to olive groves and vineyards.