Yemeni President Ali Abdullah Saleh signed a Gulf initiative on Wednesday to hand over power to his deputy as part of a proposal to end months of protests that have pushed the Arab country to the brink of civil war.
Saudi state television broadcast live images of Saleh signing the accord in the presence of Saudi King Abdullah and Crown Prince Nayef. Yemeni opposition officials signed the accord after Mr. Saleh.
It was the fourth attempt to wrap up a power transfer accord that Saleh backed out of on three previous occasions at the last minute, fueling turmoil that has bolstered al Qaeda militants next door to Saudi Arabia, the world's No. 1 oil producer.
Activists who have camped in central Sanaa have demanded Saleh end his 33 years of rule now.
Government troops skirmished with gunmen loyal to a powerful opposition tribal leader in the capital and some clashes were reported in the southern city of Taiz.
"The president ... arrived this morning in Riyadh on a visit to the Kingdom of Saudi Arabia, following an invitation from the Saudi leadership, to attend the signing of the Gulf initiative and its operational mechanism," state news agency Saba reported earlier.
Under the GCC plan, Saleh will shift all his powers to his deputy, Abd-Rabbu Mansour Hadi, who would form a new government with the opposition and call for an early presidential election within three months.
Months of protests have rekindled conflicts with Yemen's Islamist militants and separatists, threatening anarchy in a country Washington regards as a front line against Al Qaeda.
The unrest has also raised fear of civil war on the borders of Saudi Arabia, a crucial strategic ally of the United States. The fears are shared by Saleh's erstwhile US allies, who had long backed him in their fight against al Qaeda.