Spanish PM Mariano Rajoy is facing renewed calls to resign after El Mundo newspaper published text messages allegedly linking him to Luis Barcenas, the man at the centre of a secret payments scandal.

The El Mundo report said Mariano Rajoy sent words of support to Luis Barcenas, former treasurer of the governing Popular Party (PP).

Lui Barcenas is in custody facing trial for corruption and tax fraud. He denies the allegations.

Mariano Rajoy, too, denies any wrongdoing.

The PP’s former treasurer was due to appear before a judge on Monday, a week after he admitted for the first time that handwriting in a ledger detailing payments belonged to him.

A series of newspaper allegations that Mariano Rajoy and other top politicians received illicit payments has enraged a country in the depths of recession and record unemployment.

It is claimed that Luis Barcenas ran a PP slush fund that took donations from construction magnates and distributed them to party leaders in cash.

PM Mariano Rajoy is facing renewed calls to resign after El Mundo newspaper published text messages allegedly linking him to Luis Barcenas

El Mundo newspaper said last week it had delivered documents with Luis Barcenas’s original ledger entries to the High Court.

Another Spanish paper, El Pais, published similar documents earlier this year.

The leader of the country’s main opposition Socialist Party, Alfredo Perez Rubalcaba, called for Mariano Rajoy’s immediate resignation on Sunday “given the unsustainable political situation in Spain”.

“Mr. Rajoy’s conduct in this situation can be summarized quite simply: silence, lies, and after what we have learned today, collusion, extremely serious collusion,” Alfredo Perez Rubalcaba said.

El Mundo‘s most recent report includes a text message Mariano Rajoy apparently sent to Luis Barcenas in January this year – when the slush fund allegations broke.

He said: “Luis, I understand. Stay strong. I’ll call you tomorrow. A hug.”

The paper said the conversations showed Mariano Rajoy maintained “direct and permanent contact” from at least May 2011 to March 2013.

Luis Barcenas is being investigated over allegations he stashed up to 48 million euros in secret Swiss bank accounts. Prosecutors allege that some of the funds stem from illegal party donations or kickbacks.

He and his wife are also suspected of falsifying documents on their tax statements between 2002 and 2006.

Luis Barcenas and his wife deny the charges.

In June, a judge ordered Luis Barcenas to be held in jail until his trial starts after prosecutors argued that he was a flight risk.

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