U.S. President Donald Trump met with executives from some of the world's largest oil companies at the White House on Friday to discuss Venezuela, saying he wants them to invest $100 billion in the country to vastly expand its production.

The U.S. is the world’s top oil producer. Venezuela has the world’s greatest oil reserves. Donald Trump has threatened Colombia and Mexico – two Latin American countries with fairly rich oil supplies.

President Trump has set his sights on Venezuela's vast oil reserves, the largest in the world. If consolidated under Washington’s influence, about one third of global oil reserves could end up under US control.

Donald Trump now says he wants American companies to take over Venezuelan fields in order to extract and sell resources.

Militia groups outside Caracas' control could endanger oil workers, while a drop in crude oil prices makes it harder for companies to recoup investments.