Houthi attacks on Israel-linked ships since the start of Israel's war on Gaza have disrupted global trade through the Red Sea, actions the rebels say are in solidarity with the Palestinians.

The Houthis have repeatedly said they would halt their offensive once a ceasefire is reached in the Israeli war and humanitarian aid is allowed into Gaza.

Representatives from Hamas. the Islamic Jihad and the Popular Front for the Liberation of Palestine met last week with the Houthis in Beirut, the official said on condition of anonymity.

Palestinian sources on Friday told AFP that the meeting had taken place, with one of the sources saying the representatives discussed "mechanisms to coordinate their actions of resistance" for the "next stage" of Israel's war on Gaza, now in its sixth month.

Another Palestinian source, also requesting anonymity to share details of the meeting, told AFP that those present discussed the "complementary role of Ansar Allah (the Houthis) alongside Palestinian factions, especially in the event of an Israeli offensive on Rafah".

Most of the Gaza Strip's 2.4 million people have sought refuge in Rafah, on the coastal territory's southern border with Egypt, the last major urban area spared an Israeli ground invasion.

Israeli Prime Minister Benjamin Netanyahu's office said on Friday he had approved the military's plan for a so-called ground operation in the city, without providing a timeline.

In a speech Thursday, Houthi leader Abdul Malik al-Houthi threatened to expand the group's offensive to target ships avoiding the Red Sea and Gulf of Aden by sailing south around Africa.