President Donald Trump’s call for U.S. oil companies to rebuild Venezuela’s energy sector after the overthrow of President Nicolás Maduro is easier said than done.

Chevron Wall Street analysts say the company has an advantage as the only major U.S. oil company currently operating in Venezuela. Exxon Mobil and ConocoPhillips They left the country in 2007 after former President Hugo Chavez nationalized the industry and confiscated their assets.

Venezuela has the world’s largest proven crude oil reserves, at 303 billion barrels, according to the U.S. Energy Information Administration. But U.S. oil majors still have a long and expensive road ahead for Venezuela to return to the peak production of 3.5 million barrels per day reached in the 1990s.

“This is a high-risk investment area for oil companies,” said Arne Lohmann Rasmussen, principal analyst and head of research at Global Risk Management.

Consulting firm Rystad Energy estimates that approximately $53 billion in investment will be needed over the next 15 years to maintain crude oil production levels of 1.1 million barrels per day. Rystad said capital expenditures needed to reach 3 million barrels per day by 2040 will more than triple to $183 billion.

certainty and stability

Rapidan Energy founder Bob McNally said U.S. oil majors want certainty about who is in charge in Caracas and the stability of the government.

David Goldwyn, who served as the State Department’s special envoy for international energy affairs from 2009 to 2011, said they need to know whether the legal and fiscal systems are sustainable in the long term because energy investment is a 30-year project.

The current situation in Caracas is uncertain. Trump announced on Saturday that the United States would govern Venezuela after Maduro is overthrown. Secretary of State Marco Rubio There seems to be a withdrawalIn an interview with NBC News on Sunday, he said the United States would use its influence to pressure Caracas to meet U.S. demands.

Vice President Delcy Rodriguez takes power in Venezuela, promising over the weekend that the government will Protect national resourcesbut later said Caracas sought cooperate with the United States

Global Risk Management’s Rasmussen said a major question is whether Venezuela will return to a Maduro-like regime in the future and nationalize oil assets again.

Surplus reserve

McNally, a former White House energy adviser under President George W. Bush, said U.S. oil majors will grapple with whether it makes economic sense to invest tens of billions of dollars in Venezuela when there is already so much oil in the world.

“There are a lot of reasons to think this is going to be a long and winding road, not a fast one,” McNally said.

Chevron maintains a joint venture with state-owned Petroleos de Venezuela SA through a special license issued by the U.S. government. According to JPMorgan, these partnerships account for about 23% of Venezuelan output.

“The company will be well-positioned to potentially expand future production as they own significant oil resources through joint ventures and have been a major developer of energy infrastructure in the country,” JPMorgan analyst Arun Jayaram told clients in a note on Monday.

Chevron shares rose more than 5% on Monday.

—CNBC’s Hayley Cuccinello contributed to this report.