A series of equipment and investment issues in Venezuela have seen the country’s exports of crude oil fall 9% on the month.

Two power blackouts and equipment outages throughout August impacted the flow of oil, with state energy company Petróleos de Venezuela’s (PDVSA) investment plans still being hit by US sanctions.

This has lead to ongoing operational problems, according to several US media reports, citing shipping data.

Venezuela has the world's largest proven oil reserves at just over 300 million barrels, and was at one time one of the world’s largest oil exporters.

The blackouts caused the suspension of refinery operations and port activities. This was followed by several equipment issues.

Around 40 vessels left the South American nation’s ports in September, carrying more than 840,000bopd, according to the shipping data, markedly below the previous month’s levels.

Venezuela is still attempting to increase it oil output, and late last year PDVSA and Repsol, the Spanish multinational energy and petrochemical company, signed a new agreement for their joint venture to increase oil and gas output in Venezuela.

The agreement was for Petroquiriquire, an entity with operations in the Quiriquire oilfield in the state of Monagas, as well as the Mene Grande and Barúa Motatán fields in the states of Zulia and Trujillos, respectively.

PDVSA has a 60% stake in Petroquiriquire and the Spanish oil and gas producer owns the remaining 40%.