iStock/grynold(CARACAS, Venezuela) -- Venezuela's opposition has declared talks with its strongman president Nicolás Maduro dead after weeks without meetings -- a decision meant to bring renewed international pressure, but that appeared to crack its united front.

One day after the opposition leader, who the legislature has declared is the legitimate president, said talks were off, minority parties in the legislature signed an agreement with top Maduro officials to move forward with new negotiations.

The U.S. welcomed the decision by Juan Guaidó, the president of Venezuela's National Assembly which declared Maduro illegitimate in January. But days after the U.S. touted the opposition's unity, the new rift appears to threaten the Trump administration's road map ahead.

Guaidó's mission to the U.S. downplayed the announcement, denouncing the parties as "fake opposition" who have been supporting Maduro and adding that they, "in no way weaken the legitimate government of Interim President Juan Guaidó."

Norway had been brokering talks held in Barbados to resolve the political crisis and the humanitarian catastrophe that has driven over 4 million Venezuelans from the country, led to hyperinflation and massive shortages of food and medicine, and increased tensions in the region.

But those talks have been dead since early August after the U.S. imposed an economic embargo on Maduro, freezing all Venezuelan assets in America's jurisdiction and allowing the U.S. to impose sanctions on anyone doing business with Maduro.

"The regime is the main obstacle to a political solution. It is imperative that everyone -- inside and outside Venezuela, together -- increase the pressure," Guaidó said on Sunday.

Specifically, the opposition hoped to use the declaration of an end to talks to push the European Union to impose greater sanctions on Maduro and his officials, Guaidó's envoy in Washington, Carlos Vecchio, told ABC News. Maduro and his allies have used European banks to help skirt the stringent U.S. sanctions, while the E.U. has sanctioned only 18 officials so far, according to Vecchio.

"We need to increase the level of pressure in the international arena and also domestically, internally," Vecchio said, adding that the opposition will push for greater demonstrations inside Venezuela in the coming weeks and for new institutional pressure through the National Assembly.

To boost that campaign and rally more international attention and pressure, Guaidó is also considering attending the United Nations General Assembly next week, Vecchio said. It would be a bold journey overseas, only his second since being declared interim leader and one complicated by the difficult secret journey required to exit and re-enter the country.

Maduro announced last Thursday that he would not attend the global meeting in New York, prompting speculation that his grip on power may be too tenuous for him to even leave the country.

But over nine months after this political crisis began, Maduro maintains control of the government and is still recognized by the U.N., although the U.S. and over 50 other countries recognize Guaidó as the legitimate leader. In particular, it's Maduro's enduring sway with the Venezuelan armed forces and its leadership that has kept him in command.

The announcement of a deal with a small group of National Assembly lawmakers could help boost his image as working with the opposition to solve the crisis, according to analysts.

Representatives of several opposition parties signed an agreement with Maduro's communications minister and other officials to reform the country’s electoral board, according to the Associated Press, and begin negotiations over the pro-government Constitutional Assembly, which Maduro created in 2018 to rival the opposition-controlled National Assembly.

Guaidó called the announcement a "maneuver" by Maduro to split the opposition and stall for time, noting previous engagements with him have failed to reach any resolutions, according to the Associated Press. Vecchio's spokesperson told ABC News in an email that Maduro is "set[ting] up a fake negotiation with collaborationist parties to raise a false agreement that does NOT call for new presidential elections."

Before talks disbanded last month, Guaidó's side offered a detailed road map on how to move forward, including creating a transitional government headed by neither man and allowing free elections with international monitors nine months later, Vecchio said.

Maduro rejected that proposal. But now, with diplomacy seemingly dead and both sides digging in, it's unclear what path there is for the opposition and U.S. to remove Maduro.

Vecchio said Monday they are "looking for a peaceful solution," but remain open to "whatever we can do to put more pressure on" Maduro, including a naval blockade and other "military options."

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