The Organisation of American States (OAS) passed a resolution Wednesday condemning "grave and systematic" human rights abuses in Venezuela, and demanded an independent investigation.
The regional security body, which comprises every country in the western hemisphere but Cuba, passed the resolution by a 21 to 3 vote.
Seven members abstained and three were absent for the vote.
The resolution echoed charges of torture, extrajudicial killings and force disappearances made last month against Venezuela's leftist regime by UN human rights chief Michelle Bachelet.
It condemned "the grave and systematic violations of human rights in Venezuela, including the use of torture, illegal and arbitrary detentions, extrajudicial executions, forced disappearances and the denial of the most basic rights and necessities, especially those related to health, food and education."
It also called for "an independent, exhaustive and credible investigation" to bring the perpetrators to justice, and demanded that Venezuela grant "immediate and unhindered" access to the Inter-American Commission on Human Rights.
The commission, an autonomous body of the OAS, has been unable to visit Venezuela since 2002, during the presidency of Maduro's predecessor and mentor, the late Hugo Chávez.
The US representative Alexis Ludwig said the vote was "an important call to action."
The resolution was presented by Argentina, Brazil, Canada, Chile, Colombia, Costa Rica, the United States, Guatemala, Paraguay and Peru.
The United States has led an international effort to force the resignation of Venezuela's President Nicolás Maduro to clear the way for elections.
But Maduro has so far manage to survive a challenge from US-backed opposition leader Juan Guaidó, a short-lived military uprising and massive street protests.
Under Maduro, the once-rich oil producer has spiraled into a severe crisis that has driven millions of Venezuelans to leave the country.