* Veteran leader under growing pressure to quit
* Thousands protest, more expected to join in
* Wants to stay on till new constitution approved
* Army, some ruling party officials back protesters
Hundreds of thousands of Algerians rallied on Friday to demand the immediate resignation of President Abdelaziz Bouteflika, who is fighting for his political survival in the face of relentless protests and the desertion of long-time allies.
In heavy rain, protesters brandished Algerian flags and pamphlets. Police trucks were deployed but there were no reports of clashes between security forces and crowds that packed downtown Algiers.
"We stay here until the whole system goes," said Mahmoud Timar, a 37-year old teacher.
Bouteflika, 82 and rarely seen in public since suffering a stroke five years ago, bowed to the protesters last week by reversing plans to stand in elections for a fifth term and promising reforms to make the political system more inclusive.
But he stopped short of quitting and said he would stay on until a new constitution is adopted, effectively extending his present term. The move further enraged Algerians, and many of Bouteflika's allies turned against him.
"We are close to victory. The system is divided," said restaurant owner Rachid Zemmir, 55, at Friday's rally.
Bouteflika has a track record of consolidating power by outmanoeuvring anyone seen as a threat. First elected president in 1999, he wrested power from the secretive military-based establishment known as "le pouvoir” (the power).
In 2015, Bouteflika sacked powerful intelligence chief Mohamed Mediene, dubbed "Algeria's God". Last year he dismissed about a dozen top military officers.
In the most significant development in a month of demonstrations, Chief of Staff Lieutenant General Ahmed Gaed Salah threw the army's weight behind the protesters on Wednesday, saying they had expressed "noble aims".
That was a major setback for Bouteflika, who bolstered his position over the years with the help of the army and oligarchs who funded his election campaigns.
"The people and the army are brothers," protesters chanted on Friday.
Soldiers have stayed in their barracks through the unrest.
The generals have intervened in the past at momentous times, including cancelling an election which Islamists were poised to win in 1992, triggering a civil war in which an estimated 200,000 people were killed.
Some members of the ruling National Liberation Front party, known by its French acronym FLN, have also sided with the protesters. But Algerians want to dismantle the entire moribund political system.
"FLN, go," protesters chanted.
In the past, Bouteflika and his inner circle of fellow veterans of the 1954-1962 war to end French colonial rule, FLN officials and the military skilfully managed crises.
Algerians complain that Bouteflika, who joined the struggle against France in the 1950s at the age of 19, is out of touch and living in the past.
Algeria is a major oil and gas producer, and when the "Arab Spring" revolts toppled autocrats in neighbouring countries, Bouteflika used oil revenues to secure loyalty.
Algerians with dark memories of the civil war in the 1990s set aside the same frustrations that triggered revolts elsewhere, giving Bouteflika breathing space.
But the price of crude oil has dropped over the years and the young are desperate for jobs, and an end to nepotism.
Bouteflika said in a speech in 2012 that it was time for his generation to hand over to new leaders. Many Algerians believe his brother Said is now effectively running the show.
Even if Bouteflika quits, it is not clear if the swelling protest movement can take on the secretive network of ruling party leaders, business tycoons and army generals long regarded as omnipotent.
These figures may be happy to see Bouteflika go but are likely to resist any major changes, as they have done before.