Mexican President Andres Manuel Lopez Obrador on Tuesday appealed to the Senate for a referendum on whether to prosecute five of his predecessors over allegations that include graft.

Speaking at his daily press conference, Lopez said that Mexicans should decide whether the five former presidents — Carlos Salinas, Ernesto Zedillo, Vicente Fox, Felipe Calderon and Enrique Pena Nieto — should stand trial. 

He accused them of presiding over "excessive concentration of wealth, monumental losses to the treasury, privatization of public property and widespread corruption," blaming their neoliberal policies. 

Read more: Mexico's former president Pena Nieto accused of receiving bribes

Calderon reacted by saying Lopez Obrador "is mistaking the Republic for a Roman Circus."

"Instead of going to the prosecution with evidence, he asks the crowd whether to convict or pardon innocents, showing a thumb up or down," he wrote on Twitter. "A setback to thousands of years of justice."

Mexican law gives the president the right to request a referendum. The Supreme Court then decides whether it is constitutional.

Lopez Obrador proposed the referendum be held on June 6, 2021 to coincide with legislative elections.

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The ex-boss of the state oil company Pemex, Emilio Lozoya, named Pena Nieto, Calderon and Salinas during his corruption trial linked to Brazilian construction giant Odebrecht.

Mexico is considered among the world's most corrupt countries, ranking 130 out of 180 in Transparency International's Corruption Perceptions Index.

The left-wing populist Lopez Obrador, who came to power in 2018, has vowed to end corruption in the country and has called on his predecessors to testify in court.

dvv/dr (AFP, dpa)