(CNN) Venezuela has shut a key maritime border and grounded flights as the opposition party seeks to import foreign aid to the crisis-hit South American country.

A government representative confirmed Venezuela has closed its maritime border with Aruba, Curacao, and Bonaire and, in the Western state of Falcon, prevented flights leaving from or departing to those islands.

Vice Admiral Vladimir Quintero, a military general from embattled President Nicolas Maduro's government, said that there was no date set for lifting the closures, according to the representative.

Maduro has so far refused to allow aid trucks into Venezuela from neighboring countries, which have formally recognized the government of the self-declared interim president, Juan Guaido

Venezuelan opposition leader and self-declared acting president Juan Guaido leaves the National Assembly in Caracas after attending a meeting with ambassadors.

Despite being an oil-rich country, the Venezuelan economy has suffered from years of mismanagement.