Maduro's comments late Friday came after his chief prosecutor opened an investigation against Vanessa Neumann, the top envoy in London for opposition leader Juan Guaidó, who is recognized as Venezuela's rightful president by the U.S., United Kingdom and four dozen other nations.
"Until they rectify their position, they won't see our faces," Maduro said in a televised meeting with aides. Talks on ending Venezuela's political stalemate had been taking place under the sponsorship of Norway since April. But Maduro last month broke off the talks taking place on the Caribbean island of Barbados over the opposition's support for tougher U.S. sanctions to punish companies from third countries that do business in Venezuela.
On Thursday, Venezuelan Vice President Delcy Rodríguez released months-old recordings in which Neumann can be heard urging a Guaidó aide, Manuel Avendaño, to have the opposition stop mentioning Venezuela's claim to the Essequibo region of Guyana.
In the purported recording, Neumann says that after speaking with the British Foreign Office, she recommends that the opposition "drop the topic" of Venezuela's claim to Essequibo in order to secure London's political support. Guyana is a member of the British Commonwealth.
Neumann later responded with a tweet, saying, "For the record: I have never recommended dropping the historic claim of my country Venezuela over the Esequibo. Maduro's regime & the Cuban G2 are spreading fake news," she said, referring to the Cuban intelligence agency.
The recording was made before Guaidó, head of the opposition-controlled congress, declared himself Venezuela's president in January, arguing that Maduro's re-election was fraudulent and unconstitutional.
But the recording nonetheless appeared to have touched a nationalist nerve among Venezuelans — one shared by even Maduro's fiercest opponents. Venezuelans have long claimed a mineral-rich region west of the Essequibo River in Guyana, contending it was stolen from their country in the 19th century breakup of the former British colony, a view reflected since the 1970s in maps showing as much as 40% of Guyana as Venezuelan territory.
In announcing charges Friday, Venezuela's chief prosecutor, Tarek William Saab, accused Neumann and Avendano of secretly negotiating a deal to drop Venezuela's claim to Essequibo in exchange for lucrative contracts with multinational corporations.
Hours later, Avendano entered the Chilean ambassador's residence in Caracas, joining a long list of opposition activists who have sought protection at foreign embassies. Guaidó shrugged off Maduro's comments.
"They aren*t going to confuse or distract us," Guaidó said at an event Friday in the eastern state of Anzoategui. He said Maduro has done far greater damage to Venezuela's sovereignty by providing shelter to Colombian rebels and drug trafficking groups.
Maduro's interest in the disputed Essequibo area has increased since ExxonMobil in 2015 made one of the world's largest oil discoveries off the coast of sparsely populated Guyana.