Speaking at a televised campaign event on Saturday, Maduro said the plot also involved “right-wing forces” from El Salvador, which had already dispatched paid assassins to Venezuela to implement the plan.

“Their goal is to kill me,” said Maduro, who had been designated by the late Venezuelan leader Hugo Chavez as his heir apparent. “They want to kill me because they know they cannot win free and fair elections.”

Mr Maduro also claimed a centuries-old curse would fall on the heads of those who do not vote for him in next week’s election to pick a successor to late leader Hugo Chavez.