(CNN) - The US Department of Homeland Security announced Wednesday that it is suspending "all commercial passenger and cargo flights between the United States and Venezuela" indefinitely.
Secretary of State Mike Pompeo has approved the suspension and Transportation Secretary Elaine Chao has implemented it, according to a statement from DHS.
"This determination is based on the ongoing political instability and increased tensions in Venezuela and associated inadvertent risk to flight operations," the statement said, noting a concern for the safety of passengers, crew and aircraft.
A State Department official confirmed the suspension of passenger and cargo flights due to security concerns.
"On May 15, the US government announced that all nonstop flights between the United States and Venezuela are suspended, effective immediately, due to security concerns," the official told CNN.
"As a result of the Maduro regime's inability to govern and perpetuation of lawlessness, it is no longer possible to certify that Venezuela is meeting baseline standards of security," the official added, referring to embattled President Nicolas Maduro.
All commercial passenger flights from the US to Venezuela had already been suspended by the individual airlines.
American Airlines was the last to suspend its flights, ending its Miami-Caracas flight in March.
The State Department is also advising US citizens who are in Venezuela to leave the country if they can do so safely, "via any available means."
Wednesday's announcement comes as Venezuelan opposition leader Juan Guaido is calling more openly than ever for US assistance, while he continues to seek fresh elections in the country.
Guaido is Venezuela's National Assembly president, recognized as the country's legitimate interim president by more than 50 countries, including the United States. As momentum slows in the nationwide protests that he regularly organizes, Guaido has begun to eye new strategies for political change.
In a letter posted early Monday, Carlos Vecchio -- Guaido's appointed ambassador to the US -- requested a meeting between the US Southern Command and Guaido's representatives.
The May 11 letter was addressed to US Adm. Craig S. Faller, who heads the Southern Command and had previously voiced support for Guaido's movement on the official Twitter account of the Southern Command.
Venezuela's opposition movement would "welcome strategic and operational planning so that we may fulfill our constitutional obligation to the Venezuelan people," Vecchio wrote to Faller. The letter did not call for military action specifically.
For months, the US has refused to rule out military action in support of Guaido's movement. However, US President Donald Trump has also urged caution among senior advisers moving forward, and expressed frustration that some aides were openly hinting at a US military intervention in Venezuela, according to officials familiar with the matter.
CNN's Flora Charner and Tatiana Arias contributed to this report.
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