President Nicolas Maduro on Saturday accused the United States of using frozen Venezuelan funds to bankroll mercenaries to assassinate him in a "plot" he said was directed by opposition leader Juan Guaido.

"We have dismantled a plan organized personally by the diabolical puppet to kill me," Maduro told thousands of supporters in Caracas, referring to Guaido, who is recognized as interim president by more than 50 countries.

He alleged that Colombia, Venezuela's US-aligned neighbour, was also involved, and said that an unidentified Colombian paramilitary chief had been captured in the country "and is giving testimony."

Maduro's government gave details of the alleged plot on state television, with Information Minister Jorge Rodriguez saying "hitmen" from El Salvador, Guatemala and Honduras had been recruited "using big sums of money" and sent to Colombia ahead of missions into Venezuela to carry out "targeted assassinations" and "sabotage."

Rodriguez accused Guaido's chief of staff, Roberto Marrero, of receiving money from the United States and being a key organiser of the alleged operation.

Marrero, a 49-year-old lawyer, was arrested on Thursday in his Caracas home, triggering an outcry and demands he be immediately released by the US, the European Union and major Latin American countries that recognize Guaido as Venezuela's interim president.

He yelled out to a neighbour, an opposition lawmaker, that the SEBIN intelligence officers arresting him had planted two assault rifles and a grenade in his home. Hours later, Maduro's government showed pictures of weapons it said it found and alleged Marrero was part of a "terrorist cell."

Rodriguez played recordings he said were from WhatsApp conversations between Marrero and Guaido in which he said they discussed using Venezuelan funds blocked by US sanctions to finance armed groups with the support of Colombian President Ivan Duque.

The accusations were repeated shortly afterwards by Maduro as he addressed a crowd of thousands of supporters in the capital.

According to his government, the United States has seized USD 30 billion is Venezuelan assets, including money in bank accounts. Rodriguez alleged funds in accounts in Bank of America and Banesco Panama were being used in the plot.

Guaido, the head of the opposition-run assembly, has asked the international community to keep up its pressure on Maduro's government.

The United States has ratcheted up successive rounds of sanctions on Venezuela, suspending visas for 300 Venezuelans deemed close to the regime and making it difficult for the state-run oil company PDVSA to operate or secure credit on the markets.

On April 28, the sanctions will jump up another level with an embargo on crude exports.

US President Donald Trump's administration has repeatedly warned Maduro to not arrest or intimidate Guaido or his aides, or else face unspecified consequences.

Trump has reiterated that "all options" -- implicitly including military action -- are on the table for dealing with Venezuela.

(This story has not been edited by Business Standard staff and is auto-generated from a syndicated feed.)