The agreement would make President Ali Abdullah Saleh the fourth dictator pushed from power this year by the Arab Spring uprisings, although it has been rejected by many protesters because it would grant the reviled leader immunity from prosecution and does not include far-reaching political changes like those brought about by the uprisings in Tunisia, Egypt and Libya.

The US-backed Gulf Arab proposal signed Wednesday in the Saudi capital Riyadh calls for Saleh to pass power to his deputy within 30 days, after a new government sworn in by the vice president passes a law protecting Saleh and his associates from prosecution.

Presidential elections also are to be held within 90 days, well ahead of the original date in 2013.

It came after months of resistance by the leader of 33 years despite massive protests calling for him to step down. Saleh had agreed to sign the deal at least three previous times only to back out at the last minute.

Vice President Abed Rabbo Mansour Hadi said Saturday that the vote will be held on Feb. 21 and no party has the right to annul or change the decree, SABA reported. He made the announcement after Saleh gave him "the constitutional authorities to carry out dialogue with the parties that signed the Gulf initiative."

While it was welcomed by the US, which fears instability in the country that's home to one of the world's most active al-Qaida branches, the agreement has failed to end the mass protests that have rocked Sanaa and other cities since February.