Venezuelan President Nicolas Maduro is facing a new threat from an unlikely place: old-school leftists who accuse him of betraying the socialist legacy that carried him to power.

Maduro was tapped by Hugo Chavez as his preferred successor to the presidency, but orthodox socialists are grumbling over liberalized currency reforms they say are counter to the revolution.

The tensions came to a head last week when Maduro fired Planning Minister Jorge Giordani, a Marxist economist whose Spartan lifestyle and anti-capitalist doctrine earned him the nickname "the Monk."

Giordani then published a tract accusing Maduro of undoing Chavez's gains and failing to control his administration.