In a televised address, Abdul Malik al-Huthi condemned Israeli strikes on Lebanon, saying they aim to block Hezbollah, also backed by Iran, from "supporting Gaza and the Palestinian people".

Since November, the Huthis have targeted Red Sea shipping with drones and missiles, saying it was in solidarity with Palestinians in the Israeli war on Gaza which was sparked on October 7.

Israel this month said it was shifting its military's focus from Gaza to Lebanon.

Lebanon said on Thursday that 1,540 people have been killed in Israel's intensified strikes this week.

The Houthi chief described Israel's action in Lebanon as "pre-planned aggression" that had been "in place for years" while asserting Hezbollah was "stronger than ever before".

Drawing on the 2006 Israel-Lebanon war, he warned any "ground operation in Lebanon will inflict heavy losses on the enemy and its inevitable result will be a great defeat".

The Houthi leader added that Hezbollah's missiles could hit all parts of "occupied Palestine".

The Houthis are fighting Israel as part of Iran's "Axis of Resistance", which includes Hamas, Lebanon's Hezbollah and several Iraqi Shia Muslim groups.