The streets of Yemeni capital Sanaa, which had rung with gun and rocket fire in recent days, were mostly quiet early on Sunday after President Ali Abdullah Saleh flew to Saudi Arabia for medical treatment.

Saudi sources said Riyadh had brokered a ceasefire between rival clans and political elites. A few small gatherings celebrated Saleh's departure in Sanaa.

The Saudi royal court said Saleh had arrived to be treated for wounds suffered in Friday's rocket attack on his presidential palace -- an assault that marked a major escalation in a conflict building towards full civil war.

Rumours of Saleh's departure had circulated in Sanaa for hours before his arrival in Riyadh was confirmed, and Yemeni officials repeatedly denied he had any plans to leave.

'These are the most difficult days and we're worried the coming days will be even more difficult,' Sanaa resident Ali al Mujahid, 42, said. 'We want them to solve their conflicts and leave us to live in peace.'

Saleh, whose Saudi medical evacuation plane was met by a senior Saudi official, walked off the aircraft but had visible injuries on his neck, head and face, a source told Reuters.

Saudi Arabia, itself vulnerable to religious militant groups operating on Yemeni territory, has been to the fore in efforts by Gulf states to negotiate Saleh's resignation and peaceful handover of power to fractious opposition groups. He has several times backed away from agreements at the last moment.

The world's top oil exporter shares a 1,500-km (950-mile) border with Yemen, and until recently with the United States had backed Saleh as an ally against a Yemen-based arm of Al Qaeda.

'I think this is just about the end of his match,' Khalid al-Dakhil, a Saudi political analyst, said. 'The Saudis are not going to bargain with him.'

Leaving Yemen at a time of such instability, even for medical care, could make it hard for Saleh to retain power. Al Jazeera television said Saleh's vice-president, largely a figurehead, was taking over as acting president and head of the armed forces in Yemen.

US President Barack Obama's top counter-terrorism aide spoke on Saturday with Yemen's vice-president, Abd-Rabbu Mansour Hadi, the White House said, without offering details of the talks. Washington has been calling for Saleh to leave.

The true seat of power, following Saleh's departure, has yet to be decided. But Saleh's eldest son, Ahmed, commands the elite Republican Guard and three of his nephews control the country's security and intelligence units.

It was not clear if Saleh's sons and nephews were among the 35 relatives who accompanied Saleh to Saudi Arabia. If confirmed this suggests Saleh may not plan to return.

Saleh was transferred to a military hospital after landing at King Khalid Air Base, a Saudi source said.

He will have tests before surgery to remove shrapnel from his body, the source said, adding Saleh was also expected to have plastic surgery to mend wounds on his face and neck.

The rocket attack, which killed seven people, devastated the government. The prime minister, two deputy prime ministers and the speakers of both parliamentary chambers are being treated in Riyadh for injuries.

The latest violence, which pitted Saleh loyalist forces against members of the powerful Hashed tribe led by Sadeq al-Ahmar, was the bloodiest since pro-democracy unrest erupted in January and was sparked by Saleh's refusal to sign a power transfer deal.

A Saudi official said Saudi Arabia had brokered a fresh truce between a the Hashed tribe and forces loyal to Saleh, and a tribal leader said his followers were abiding by it. - Reuters