Is Spain's opposition plotting to oust weakened PM soon?

The minority left-wing coalition government suffered a harsh blow on Monday with the jailing of ex-Socialist heavyweight Santos Cerdán for alleged corruption.

The case has also ensnared former transport minister José Luis Ábalos, another of Sánchez's former right-hand men who helped propel him to power in 2018.

Few doubt the existence of the alleged murky dealings after media published audio recordings which discussed the payment of kickbacks for the awarding of public contracts and the description of prostitutes.

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Separate investigations are underway into Sánchez's wife and brother, heightening speculation that the survival instincts of a leader who came to office promising to eradicate corruption will finally succumb.

The rival Popular Party (PP) congress in Madrid was already scheduled but has now taken on more importance while the Socialists try to resolve the political bombshell of the corruption scandal.

The centre-right formation will re-elect Alberto Núñez Feijóo as leader and set the stage for new secretary general Miguel Tellado, an abrasive figure who calls the Socialists a "mafia" and Sánchez a "capo".

With these and other changes, the PP "will look more like a group of hooligans than a moderate conservative party", the Socialists retorted.

'Faux pas risk'

The PP smells blood with the Socialists in a moment of weakness, but toppling the government and triggering early elections is fraught with difficulty.

Although the PP has the most seats in parliament following the last vote in 2023, Feijóo has avoided filing a no-confidence motion for lack of a majority.

A theoretical alliance with the far-right Vox party would not reach a majority in the 350-seat parliament and repel other potential allies.

On the other hand, Sánchez managed to stay in power in 2023 by cobbling together a motley alliance of far-left and regional separatist groups.

The influential PP head of the Madrid region, Isabel Díaz Ayuso, warned her party against "faux pas" that could end up strengthening Sánchez.

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But pressure continues to grow on Sánchez, with the PP demanding his resignation and misgivings growing among his own ranks.

Emiliano García-Page, the Socialist leader of the central Castilla-La Mancha region, told Cope radio that "there is no dignified way out" for the premier.

The Teneo consultancy predicted early elections as the most probable outcome without ruling out Sanchez's survival to the end of the government's term in 2027.

As "further revelations about the kickbacks scandal emerge, the government could lose the support of its allies," Teneo wrote in a note.

Sanchez will chair a Socialist federal committee in Madrid on Saturday that will elect Cerdán's successor, while on July 9 he will appear in parliament to give explanations on the corruption case.