(CNN) -- Venezuelan opposition leader Henrique Capriles Radonski said Thursday that he will formally contest the South American country's presidential vote "in the coming days."
In an interview with CNN affiliate Globovision, Capriles accused election authorities of lying to Venezuelans last week when they announced plans to complete a 100% audit of the election. A week later, he said, no such audit has started.
That means contesting the election before judicial authorities is the next step, Capriles said.
Last week Venezuelan election officials said Nicolas Maduro had secured 50.8% of votes in Venezuela's April 14 presidential election while Capriles won 49%.
The narrow margin has sparked mounting tensions in Venezuela after the closely watched vote to pick a successor to Hugo Chavez, who died on March 5 after a long battle with cancer.
On April 18, Venezuela's National Electoral Council said it would complete 100% audit of votes cast in the election "to preserve a climate of harmony between Venezuelans."
The next day, Maduro was sworn in as president.
Since the election results were announced, Capriles has called for a recount, alleged thousands of election irregularities and decried Maduro's government as illegitimate.
"According to the law," he told Globovision on Thursday, "what should happen would be a new election, without any of the irregularities that we have denounced."
Maduro has accused Capriles and his supporters of inciting violence. In numerous public appearances and national television broadcasts, he's vowed to use an iron fist to crack down on any coup attempts.
In nationally broadcast remarks Thursday, Maduro stressed that he had won a clear majority of votes in the election.