Yemenis tend to say that, compared with the Houthis, the danger from armed jihadist groups is exaggerated.

ECONOMIST: Yemen

At the same time, the Saudi navy is blockading the coast to stop arms reaching the Houthis by boat.

ECONOMIST: Yemen's war

But the Houthis, whose armed rebels are said to number anything from 2, 000 to 10, 000, are far from defeated.

ECONOMIST: Yemen's war

The Saudi and Yemeni governments both accuse Shia Iran of helping the Houthis, who belong to the Zaydi branch of Shia Islam.

ECONOMIST: Yemen's war

In one night engagement, the Houthis are said to have tied torches to a dozen goats and herded them into range of a Yemeni army platoon.

ECONOMIST: Yemen

The Yemeni authorities also darkly note that the Houthis' long-time leader, Hussein al-Houthi, who died in battle in 2004, used to visit Qom, one of Shia Iran's holiest cities.

ECONOMIST: Yemen's war

Reports suggest the weapons were destined for the Red Sea port of Al-Mukha, and that their intended recipients were the Houthis - a Shia insurgent group based in northern Yemen.

BBC: Yemen blames Iran after weapons haul

Unlike those loyal to Mr Zuail, they are said to have been told by an influential Jordanian jihadist cleric, Abu Muhammad al-Makdissi, that they should keep well out of the war against the Houthis.

ECONOMIST: Yemen's war

The powerful tribal chief Hamid al-Ahmar, who heads the Sunni Islamist Islah (Reform) party, is also reportedly boycotting the dialogue personally in protest at the decision to give Zaidi Shia rebels in northern Yemen, known as Houthis, most seats representing the province of Saada.

BBC: Yemen national dialogue conference begins

The Houthis, as the rebels are known after the name of a leading clan in the remote and spectacularly rugged region, have survived the repeated assaults not just of Yemen's own modern army but also, in the latest campaign, heavy bombardment by the Saudi air force's Tornadoes and F-15 fighter aircraft.

ECONOMIST: Yemen