BEIRUT — Yemeni President Ali Abdullah Saleh vowed Wednesday to step down from office before 2013 elections and to remove his son as his likely successor, an apparent concession to opposition groups ahead of a day of planned protests in the capital, Sana.

Saleh announced that that he would “”freeze”” proposed constitutional amendments that would make him Yemen’s president for life and postpone April parliamentary elections that have been widely dismissed as rigged in the government’s favor.

“”No to hereditary rule and no to life presidency,”” Saleh told parliament, according to the official Saba news agency.

“”Regardless of the circumstances, I will make concessions one after the other for the sake of this nation,”” he said in the 17-minute address. “”The interests of the homeland are above our interests as individuals, parties, groups and commissions. It is a shame for us to destroy what we built.””

Analysts said the concessions would fail to sate a boisterous opposition movement inspired by anti-government uprisings in Tunisia and Egypt. Critics note Saleh made a similar statement in 2006 about not running for re-election, only to go back on his word after supporters staged demonstrations urging him to run again.

“”The opposition doesn’t really believe in what he says,”” said Shatha Harazi, a political reporter at Sana’s independent English-language Yemen Times. “”He didn’t speak about canceling the amendments. … He’s trying to calm the anger. Once the opposition calms down, he will again discuss the elections and the amendments.””

The toppling of Tunisia’s longtime leader Zine El Abidine Ben Ali on Jan. 14 after weeks of protests, followed by the Egyptian uprising that erupted 11 days later, have galvanized calls for change across the region, including in Jordan, Libya, Syria, Algeria and Sudan.

Saleh, 64, who has served as president of the Arab world’s poorest nation since 1978, is among the most vulnerable Arab leaders.

His rule has been characterized by allegations of corruption, incompetence and nepotism. Yemen has one of the highest birthrates in the world and faces a critical water shortage. A secessionist movement has erupted in the south, an insurgency rages in the north, and al-Qaida militants have taken root in the countryside.

Yemenis also complain of stagnant wages and high food prices. A wide coalition of relatively well-organized opposition groups that includes Islamists, trade unions and leftists has called for a “”day of rage”” Thursday against Saleh. On Tuesday, Saleh’s government approved emergency financial handouts for 500,000 families and tuition exemptions for college students.

He has called for a “”comprehensive national dialogue”” with the opposition in an attempt to defuse rising anger against him.

But the opposition coalition has rejected the president’s entreaties and urged supporters to take part in nationwide protests. “”It’s expected to be huge,”” Harazi said.