Thousands Launch Anti-Bouteflika Protest In Algiers: AFP

Thousands of demonstrators have gathered in the centre of the Algerian capital for a fourth consecutive Friday demanding the ouster of President Abdelaziz Bouteflika, AFP correspondents said.

They said the crowd at Algiers' landmark Grand Poste square was growing, two hours before the scheduled start of a demonstration calling on the 82-year-old to step down after two decades in power.

The rally is the first major test of whether Bouteflika has calmed anger on the streets with his surprise announcement on Monday that he would not seek re-election but was cancelling an April presidential poll.

"You pretend to understand us, we will pretend to listen to you," read a banner held aloft by the mostly young demonstrators.

Bouteflika had initially sparked joy among protesters when he said he would not stand again, but his move to cancel the vote prompted accusations of "tricks" and sparked a new round of demonstrations.

He has also named a new prime minister, replacing unpopular premier Ahmed Ouyahia with former interior minister Noureddine Bedoui, who on Thursday defended the postponement of the poll.

The protest movement has been led by students, in a country where half the population is under the age of 30 and youth unemployment has spurred anger against a government seen as out of touch.

Bouteflika, who uses a wheelchair and has rarely appeared in public since suffering a stroke in 2013, has promised a "national conference" to carry out reforms.

The president said new elections would be held "before the end of 2019", suggesting he may stay in office for another year.