According to the managing partner of the US-based investment bank Caracas Capital Markets, Russ Dallen, who issues intelligence briefs on Venezuela, in June 2020, the Russian oil tanker Sierra entered the port of Jose, where the country’s main export oil terminal is located. The call was “so secret that the PDVSA port documents we have access to do not say for whom the ship is taking the oil, in what volume and what grade of oil,” Dallen wrote in late June in a note to his clients.

https://www.rbc.ru/economics/14/12/2020/5fce9d879a79471c1e8cb6b4