Saudi Arabia does not want anything to upset its hosting of the g20 summit in November.So Prince Muhammad hopes to disengage and lock the Houthis inside Yemen, much as Israel does with Hamas, a Palestinian militant group, in Gaza.But the Houthis sense Prince Muhammad's desperation and want a better deal.They rejected the ceasefire, while putting forward their own peace plan.It demands that Saudi Arabia lift its air and sea blockade of Yemen,pay reparations for the damage it has caused (as well as ten years of government salaries)and recognise the Houthis as the legitimate government.If the Saudis do not agree, the Houthis promise "a major escalation inside the kingdom".Analysts think they are planning a ground assault on Najran, a city in southern Saudi Arabia with a largely Shia population(albeit of a different strain from that of the Houthis).The Houthis are already pushing deeper into the Yemeni provinces on the border with Saudi Arabia.They have made gains in Jawf and are fighting in the crags above Marib, an oil-and-gas hub.Control of Marib would not only hand the Houthis valuable resources;it would also make it harder for the government and allied tribes to wage war.Government-aligned forces use bases in Marib city to launch air and ground attacks in the north.