"The cargo is in Caracas airport. We are talking about our medicines and medical equipment within the World Health Organization," the source said.
Moscow and Caracas are to hold a series of meetings at various levels on the situation in Venezuela, the Deputy Foreign Minister Sergei Ryabkov said.
"In the near future, a whole series of contacts is scheduled at various levels on various aspects of the current situation. Now the moment is alarming, and the need for this kind of interaction and close dialogue is as high as ever," Ryabkov said.
Earlier, Venezuela's President Nicolas Maduro said that Russia will deliver 300 tonnes of humanitarian aid to the Venezuelan.
Venezuela is currently facing a sharp economic and political crisis. Tensions in Venezuela escalated on 23 January, after the opposition leader, Juan Guaido, proclaimed himself an interim president of Venezuela, the United States recognized him as the country's leader and delivered aid for the country to neighbouring Colombia.
In turn, Nicolas Maduro refused to accept the US aid, blasting it as a ploy to topple his government.