Mexico diplomatic residence in Venezuela's capital took in a member of that country's opposition-controlled congress, the foreign affairs ministry said Tuesday.
"We know they will continue with this process of trying to destroy the National Assembly".
The National Assembly has come under increasing pressure from Maduro since the opposition appealed in vain for a military uprising on April 30. It cited the possible presence of an explosive device inside the building.
Last week, the Mexican government said it was concerned about the arrest of Venezuelan National Assembly deputy Edgar Zambrano for his involvement in a failed military uprising against Maduro last month.
He has previously accused the socialist leader of terrorism for his heavy-handed response to demonstrations.
The United Nations plans to appoint a humanitarian coordinator soon to oversee a rollout of aid to Venezuela.
"The future of Venezuela will be decided by the armed forces: either they stay in power with the same government or they remove Maduro", Heleno said in an interview.
Guaido's declaration that he is the country's legitimate acting president, which has been supported by more than 50 countries, plunged Venezuela into a political crisis.
The London-based rights group said at least 47 people were killed during the protests from January 21 to 25.
Amnesty sent a fact-finding mission to the country in February to research the crackdown on the anti-government protests that preceded and followed Guaido's swearing-in.
Venezuela's information ministry, which handles media inquiries on behalf of the government, did not respond to a request for comment on why security forces blocked the entrance to parliament.
It came about after the National Assembly branded Maduro a usurper over his controversial re-election past year in polls widely regarded as fraudulent.
Claver-Carone, who is one of the Trump administration's key national security advisers, said: 'One of the positive elements [of the uprising] is that there were many people involved.
Those remaining behind face shortages of basic necessities such as food and medicines, and failing public services including water, electricity and transport.
Mauricio Claver-Carone, the senior director of the White House National Security Council, told a conference in Bogota, Colombia, that Maduro is increasingly paranoid and can no longer trust his inner circle of advisers as those who were once loyal to him have moved their allegiances. Bullet-proof vehicles and a tow truck were parked in the surrounding streets.
"Whether it's in a square, in the annex buildings, under a bridge, the Assembly will sit and there will be a session", said congressman Luis Stefanelli.
The president has "brought nothing but misery to the Venezuelan people", he said in the Russian city of Sochi at joint press conference with his Russian counterpart Sergei Lavrov, who responded by saying that "threats by the USA administration" against the Venezuelan leadership have "nothing to do with democracy".