Guaido did not detail what threats he faces, but one possibility is that Maduro could order his arrest. Guiado and Bolsonaro called for a return to democracy in Venezuela, with Guaido saying he wanted free elections, monitored by international powers.
Oil-rich Venezuela was getting "closer and closer" to a change, he said. Bolsonaro said Brazil would "spare no effort" at helping Venezuela return to democracy within the law. He said his administration supported decisions made by regional leaders in Bogota earlier this week, when representatives discussed sanctions and diplomatic pressure but ruled out military intervention.
During his visit to Brazil, Guaido was also expected to meet with Foreign Minister Ernesto Araujo, leaders of Congress and ambassadors of several countries. On Tuesday, Guaido met in Colombia with regional diplomats and U.S. Vice President Mike Pence.
Guaido, the head of Venezuela's legislature, has won recognition as the country's rightful leader from more than 50 nations, including the United States, but has been unable to wrest power from Maduro.
Maduro's opponents say his re-election last year was fraudulent. His backers insist the vote was legal and say Guaido is violating the constitution. Guaido-led attempts over the weekend to bring humanitarian aid into Venezuela via neighboring Brazil and Colombia failed.