KHOBA, Saudi Arabia (Reuters) - Saudi Arabia declared victory over Yemeni rebels on Wednesday following a truce offer from the insurgents, who said they had withdrawn from Saudi territory. The worlds top oil exporter was drawn into a conflict raging between Yemens government and the rebels along the border in November, when Riyadh launched a military assault against the insurgents after they seized some Saudi territory. We achieved a clear victory, Saudi Assistant Minister of Defence Prince Khaled bin Sultan told reporters, adding that the rebels had been forced from Saudi land. We cleansed the area ... Withdrawal was not an option for them. Rebel leader Abdul-Malik al-Houthi made the ceasefire offer on Monday, two days ahead of a meeting of foreign ministers of Western powers, Gulf states, Egypt, Jordan and Turkey in London to discuss ways to stabilise Yemen as it grapples with problems on several fronts, including a growing threat from Al-Qaeda. Western powers and Yemens neighbours fear the growing chaos in the impoverished Arab country could allow Al-Qaeda to strengthen its operations there, spreading instability across the region and beyond. According to a draft document from the conference later on Wednesday obtained by Reuters, the major powers committed to supporting Yemens government and said Yemen recognised the urgent need for political and economic reforms. Yemen, also struggling to contain simmering separatist sentiment in the south, has been fighting the northern rebels on and off since 2004 but the conflict intensified last summer when the government launched Operation Scorched Earth. It was not the first time that Riyadh has claimed victory against the rebels. King Abdullah told a Kuwaiti newspaper last month that Saudi had driven away the last of the infiltrators. Prince Khaled said on Wednesday 109 Saudi soldiers had been killed since the fighting started and six were still missing, of which four were being held by the rebels. He listed three further steps the rebels must take to prove they wanted to end hostilities: rebel snipers should withdraw, the six missing soldiers should be returned and the rebels would have to pull back further from the border to create a 10-km border buffer zone inside Yemen secured by the Yemeni army. If they meet these conditions, we can then say this is an internal issue and the matter will go back to the Yemeni government to deal with it as it wishes, he added. A senior Saudi military official said Saudi Arabia was no longer exchanging heavy fire with the rebels. Last night, since they announced a ceasefire, they did not fire and we did not have any engagement, Major General Said al-Ghamdi, commanding general of first paratrooper brigade, told journalists in the border area. They are not in our lands.