A tanker truck and a huge cargo container barred access to the Tienditas bridge, which links Cucuta, Colombia to Urena, Venezuela.

Franklyn Duarte, an opposition lawmaker from the border state of Tachira, told AFP that "troops from the armed forces are blocking the pass."

The aid delivery was being coordinated by Juan Guaido, the head of the National Assembly who has declared himself interim president of the oil-rich country. Some 40 countries have recognized him as Venezuela's legitimate leader.

Venezuelan President Nicolas Maduro has refused to accept international aid, terming it an "excuse" to initiate a military intervention led by the United States.