Supporters of Spain's Sanchez call rallies, leftists abroad urge him to stay

MADRID (Reuters) - Supporters of Spanish Prime Minister Pedro Sanchez prepared on Friday to hold rallies to urge him to stay on after he announced this week he was considering stepping down as a court looks into allegations of business corruption made against his wife.

European and Latin American leftist leaders and politicians joined calls for the Socialist leader, in office for six years, not to resign.

Local branches of the Socialist party (PSOE) organized buses to bring supporters to a rally backing the prime minister planned for Saturday morning in Madrid.

Sanchez, 52, surprised both foes and allies when he said on Wednesday he was taking several days away from public duty to consider quitting. He made his announcement on the same day a court said it would investigate his wife, Begona Gomez, for influence peddling and business corruption, allegations he said were false and orchestrated by his conservative opponents.

A judge is investigating the allegations, and a separate court is considering an appeal by Madrid's prosecuting authority to dismiss the case for lack of evidence.

"I need to pause and think," Sanchez wrote in his letter to the public on Wednesday. "At this point, I have to ask myself: is it all worth it?"

The Federation of Socialist Youth circulated fliers on social media with the slogan: "Yes, Pedro, it is worth it".

Sanchez, who secured another term for the Socialists last year as leader of a minority coalition government, said he would announce his decision to stay or go on Monday.

Brazilian President Luiz Inacio Lula da Silva said on X he had spoken with Sanchez to urge him to keep carrying the torch for more "fair, prosperous and humane" governance, adding his leadership was important for the country, Europe and the world.

Colombia's President Gustavo Petro, who denounced a far-right "mud machine" seeking to halt progressive policies, also expressed support, as did Albanian Prime Minister Edi Rama and Nicolas Schmit, the lead candidate for the Party of European Socialists (PES) in European Parliamentary elections in June.

The Spanish socialists have been viewed as a bulwalk against an advancing right wing in that vote.

A European Parliament source told Reuters Social Democrats feared Sanchez could become "another Costa", referring to Portugal's Socialist Prime Minister Antonio Costa who resigned abruptly in November over an investigation into alleged influence peddling in his government's handling of lithium and hydrogen projects.

Costa, whose chief of staff was briefly arrested, has denied wrongdoing and was never charged with any crime, and the case later appeared largely to fall apart.

Sanchez's closest allies said they were confident the prime minister would stay on.

"We have no other scenario," than him continuing after his period of reflection, Cabinet Minister Felix Bolanos told reporters on Friday.

(Reporting by Emma Pinedo and Belen Carreño; Writing by Charlie Devereux; Editing by Aislinn Laing and Frances Kerry)