CNN- The United States has completed its first sale of Venezuelan oil, valued at $500 million, according to an administration official.

Additional sales of oil are expected in the coming days and weeks, the official added.

In the days since the United States attacked Venezuela and captured its president, Nicolás Maduro, earlier this month, President Donald Trump has made it clear that he plans to tap into the country’s vast oil reserves.

Trump said on Friday that the oil industry would invest at least $100 billion to rebuild Venezuela’s battered energy sector — though it’s not clear where that number came from.

The administration’s plans to capitalize on Venezuela’s oil were met with skepticism by US energy executives at the White House on Friday.

“It’s uninvestible,” ExxonMobil CEO Darren Woods told officials when discussing the obstacles to doing business in Venezuela. “There are a number of legal and commercial frameworks that would have to be established to even understand what kind of returns we would get on the investment.”

Several other executives also expressed reluctance with doing business in the embattled Latin American country. After a lengthy White House meeting on Friday, Trump and his top aides had emerged without any major commitments from companies to invest billions of dollars in the nation.

The details about the first oil sale were unclear on Wednesday, but in a statement, White House spokesperson Taylor Rogers said that “President Trump’s team is facilitating positive, ongoing discussions with oil companies that are ready and willing to make unprecedented investments to restore Venezuela’s oil infrastructure.”

On Wednesday, Reuters reported that Venezuelan crude oil was being offered at a discount to traders compared to competing oil from other countries, such as Canada.