(Bloomberg) -- U.S. sanctions against Venezuela are making successful talks with the opposition impossible, said a key ally of President Nicolas Maduro, demanding that President Donald Trump immediately act to drop them.

"The stone in the way of any negotiation is sanctions," Tarek William Saab, Venezuela’s public prosecutor, said in a rare interview at the Public Prosecutor headquarters office in downtown Caracas. "It is a shot in the foot of any negotiation because how can you negotiate with a gun pointed at your head?"

Maduro’s government earlier this month suspended Norway-sponsored negotiations with representatives of opposition leader Juan Guaido to protest fresh sanctions by Trump freezing all Venezuelan states assets in the U.S.

Previous measures to step up pressure on Maduro’s government have also included immigration restrictions and sanctions on more than 100 Venezuelan individuals, including Saab, and entities including the state-run oil company, Petroleos de Venezuela SA.

Saab said the U.S. sanctions have prevented imports of food and medicine and are in violation of international law. The measures against Venezuela, the prosecutor said, are "worse than the ones against Cuba" and seek regime change.

While endorsing the talks with the opposition, the public prosecutor, a former state governor famous for bodybuilding, called Guaido a criminal.

"The only Venezuelan state is the one you see here", Saab said while pointing to the walls of the room. He said Guaido is under investigation for declaring himself president and harming the country’s economy by backing sanctions. As a result, Saab said, Guaido may be subject to arrest.

--With assistance from Alex Vasquez and Fabiola Zerpa.

To contact the reporters on this story: Samy Adghirni in Caracas at sadghirni@bloomberg.net;Daniel Cancel in Sao Paulo at dcancel@bloomberg.net

To contact the editors responsible for this story: Patricia Laya at playa2@bloomberg.net, Robert Jameson

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