Thousands of people are expected to take to the streets in Madrid on Saturday in support of a call for change from anti-austerity party Podemos, a week after Greece elected its ally Syriza.

The "March for Change" gets under way at noon (1100 GMT) at the Plaza de Cibeles in front of Madrid city hall and will snake its way through the streets to the Puerta del Sol square.

Protesters known as the Indignants filled that square for weeks in 2011 demanding political change at the height of Spain's economic crisis, and countless more protests followed.

Podemos was already planning the rally before Syriza's victory in Greece's snap vote but party leaders hope the Greek party's success will boost turnout at its first major march, which comes ahead of a year-end general election in Spain.

"We want a historic mobilisation. We want people to be able to tell their children and grandchildren: 'I was at the march on January 31 that launched a new era of political change in Spain'," Podemos leader Pablo Iglesias said when he announced the march in early December.

Syriza beat the mainstream Greek parties, as Podemos aims to do in Spain's general election due in November.

Iglesias, a 36-year-old pony-tailed former university professor, appeared alongside Syriza's Alexis Tsipras to publicly support him during his campaign.

"What happened in Greece is historic. Everyone knows that Spain is next," Jean-Luc Melenchon, leader of France's Left Party who plans to attend the rally, said in an interview with online newspaper Publico.

Podemos was formed just a year ago, but has surged in the opinion polls with promises to fight what Iglesias calls the traditional "caste" of political leaders.

Like Syriza, Podemos has found considerable popular support by rejecting austerity programmes adopted to try to lift the countries out of deep economic crisis and targetting corruption.

It wants to prevent profitable companies from firing people, abolish private hospitals to return to a fully state-controlled health care system and enact a "significant" minimum-wage hike.

The party has struck a chord with Spaniards enraged by a string of corruption scandals, as well as public spending cuts imposed by the conservative ruling party and previously by the Socialists after the economic crisis erupted in 2008.

"This march must remove people's fear. Syriza opened the path," said Sergio Dominguez, a 33-year-old unemployed aerospace mechanic, part of a group who came by bus from the eastern city of Valencia for the march.

Spain has now officially exited recession -- the country grew by 1.4 percent last year according to provisional data released Friday -- but nearly one in four workers is still unemployed.

Salaries for many people have dropped and the number of workers on low-paid short-term contracts has soared.

Spain's street protest movement has died down since 2013 but some of the Indignant leaders formed Podemos in January 2014.

Four months later, the party won five seats in the European Parliament, with more than 1.2 million Spaniards voting for it.

Podemos has overtaken the mainstream opposition Socialist Party in several opinion polls, and in some has topped the list ahead of the conservative ruling People's Party (PP).

The Socialists and the PP have ruled Spain alternately since the country returned to democracy after the death of the dictator Francisco Franco in 1975.

Prime Minister Mariano Rajoy has warned Spaniards not to "play Russian roulette" by supporting Podemos, which he said "promises the moon and the sun" but will not deliver.

Media on left and right have gone after Podemos, accusing it of having links to Venezuela's left-wing leaders and alleging fiscal irregularities by some of its top members.

The party's leaders have promised to publish their tax returns to dispel the allegations.