MADRID (Reuters) - Spanish Prime Minister Mariano Rajoy strongly denied on Saturday allegations in the media that he and other leaders of his center-right People's Party had for years received payments out of a secret slush fund.

"I need only two words: it's false," Rajoy said in a televised address to party leaders who gathered on Saturday for an extraordinary meeting to discuss the allegations.

Rajoy said that he would publish on the party's website all of his tax declarations to clear up the scandal, after newspaper El Pais published what it said were ledgers maintained by party treasurers to register cash contributions from business leaders that were then distributed to party leaders.

(Reporting by Sarah White; Writing by Fiona Ortiz)