Yemeni President Ali Abdullah signed an agreement ending his 33-year rule on Wednesday, and has officially transferred power to the country's vice president.
Saudi Arabia's state TV showed footage of a smiling Saleh, seated next to Saudi King Abdullah in Riyadh, as he signed four copies of the proposal.
Saleh's move is the culmination of nearly nine-month of popular uprising in Yemen, which has brought the country to the brink of civil war.
Saleh had backed out of three previous attempted by the Saudis to broker the transfer of power.
The Saudi plan calls for a power transfer to Saleh's vice president, Abed Rabbo Mansour Hadi, within 30 days and early presidential elections within 90 days.
"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.
Anti-Saleh rally in Sanaa (Photo: EPA)
UN envoy Jamal Benomar, with support from US and European diplomats, managed to devise a compromise to implement the power transfer deal crafted by the six-member Gulf Cooperation Council.
The United States welcomed the deal: "The United States applauds the Yemeni government and the opposition for agreeing to a peaceful and orderly transition of power," State Department spokesman Mark Toner said.
The agreement "marks a significant step for the Yemeni people," Toner added, praising the Gulf Cooperation Council for its role in helping broker the deal, and calling for calm by all factions there.
"We urge all parties within Yemen to refrain from violence and to move swiftly to implement the terms of the agreement in good faith and in transparency," Toner said.
The United States "looks forward to strengthening its partnership" with the new leadership, he added.
AP and Reuters contributed to this report
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