An unprecedented US arrangement involving 17 Venezuelan oilfields is raising doubts among major energy companies considering investments in the country.

Under the proposed deal, private oil firm North American Blue Energy Partners (NABEP) would receive a 100-year lease on fields holding around 65 billion barrels of reserves. The US would take a 35% stake in NABEP’s parent company, receive a guaranteed 20% of production and have first refusal on the remaining output.

Concerns also center on Venezuelan businessman Alejandro Betancourt, who controls NABEP and has previously been investigated by US and European authorities over dealings with the Venezuelan government. He was never charged and has denied allegations against him.

ExxonMobil and ConocoPhillips, whose Venezuelan assets were nationalized by the government of Hugo Chavez in 2007, remain cautious and have said their requirements for legal certainty and contract sanctity have not yet been met.

Other projects are moving ahead. Chevron, Eni, ONGC and GeoPark are expected to sign agreements in Venezuela this week, while Shell and BP recently received licenses for offshore gas projects separate from the NABEP deal.

(Reuters, max)