Diosdado Cabello, widely considered the second most powerful man in embattled President Nicolás Maduro's administration, on Tuesday emphatically denied media reports that he and other high-ranking Venezuelan officials were involved in the international drug trade, Reuters said.

The Wall Street Journal reported on Monday that U.S. prosecutors were investigating Cabello and other prominent Maduro allies "on suspicion that they have turned the country into a global hub for cocaine trafficking and money laundering."

The case against the head of the Venezuelan congress was being assembled by "an elite unit" of the Drug Enforcement Administration (DEA), along with federal prosecutors in Miami and New York, the newspaper detailed. Authorities were using evidence handed over by former cocaine traffickers, informants once close to top Venezuelan officials, as well as defectors from the Venezuelan military.

Cabello was the "main target" of the investigation, an unnamed official from the U.S. Department of Justice told the Wall Street Journal.

"There is extensive evidence to justify that he is one of the heads, if not the head, of the cartel," the source alleged, speaking of "a group of military officers and top officials" thought to be involved in the international drug trade.

But the 52-year-old National Assembly president insisted such accusations were baseless, adding they were part of a U.S.-led campaign to destabilize socialism in Venezuela, Reuters noted.

"It would never occur to us to get involved in something that would hurt young people," Cabello said. "Those who today accuse me of trafficking should present one piece of proof, just one," he added.

On his weekly TV show, Maduro agreed that the allegations were part of an "imperial" and "far-right" campaign against his embattled government.

But Colleen Schwartz, the communications director for Wall Street Journal parent Dow Jones, said the newspaper stood by its story.

Venezuelan opposition leaders, for their part, demanded action, according to Reuters. Opposition leader Henrique Capriles, the former governor who narrowly lost a 2013 election to Maduro, underlined the seriousness of the charges against Cabello.

"These are grave accusations which suggest that our country has become a bridge for drug trafficking," Capriles noted.