(NewsNation) — Venezuelan oil reserves are estimated at more than 300 billion barrels — the most of any nation — but experts say many factors will determine whether the resource could be tapped efficiently in the coming years.

President Donald Trump on Saturday said the United States would take control of the reserves and “run” the South American country after special forces captured Venezuelan President Nicolás Maduro and his wife, Cilia Flores, overnight. The pair, now in the U.S., face drug-related charges in federal court.

Trump said U.S. companies would effectively operate Venezuela’s distressed, but potentially lucrative, oil industry, which was nationalized in the 1970s. Venezuelan oil reserves eclipse those of Saudi Arabia (267 billion barrels), Iran (209 billion barrels) and other big players.

But so far, what remains of the Maduro regime has rebuffed invitations to work with the U.S.

Any companies that might want to invest in Venezuela would need to deal with security concerns, dilapidated infrastructure, questions about the legality of the U.S. operation to snatch Maduro and the potential for long-term political instability, analysts told Reuters.

American firms won’t return until they know for sure they will be paid and will have at least a minimal amount of security, said Mark Christian, director of business development at CHRIS Well Consulting.

He also said the companies would not go back until sanctions against the country are removed.

“If Trump et al can produce a peaceful transition with little resistance, then in five to seven years there is a significant oil-production ramp up as infrastructure is repaired and investments get sorted out,” said Thomas O’Donnell, an energy and geopolitical strategist.

He said that would depend on everything going right, and there’s a lot that could go wrong.

“A botched political transition that has a feeling of U.S. dominance can lead to years of resistance,” said O’Donnell, who noted armed groups of citizens and guerrilla groups operate in the country.

Venezuela — a founding member of OPEC with Iran, Iraq, Kuwait and Saudi Arabia — produced as much as 3.5 million barrels per day in the 1970s, which at the time represented over 7% of global oil output. Production fell below 2 million bpd during the 2010s and averaged around 1.1 million bpd last year, or just 1% of global production.

Reuters contributed to this report.