The Trump Administration sharply escalated its enforcement of a blockade on Venezuelan oil exports on Wednesday, seizing two tankers in separate operations across the Atlantic and Caribbean and signaling that the United States intends to exert direct control over how Venezuelan oil reaches global markets.

One of the seized vessels was a Russian-flagged tanker that U.S. officials said had violated American sanctions after attempting to sail to Venezuela to load crude oil, prompting a weeks-long pursuit across the North Atlantic before it was boarded in international waters. The ship, previously known as the Bella 1 and recently renamed the Marinera, was not carrying oil at the time. Reuters first reported the interception.

Hours later, U.S. forces apprehended a second vessel, the M Sophia, described by the military as a “stateless, sanctioned dark fleet motor tanker,” in international waters in the Caribbean. Officials said the ship had been engaged in illicit activity and was being escorted to the United States for what they called final disposition.

The seizures came as Secretary of State Marco Rubio laid out the most detailed public account yet of the administration’s plans for Venezuela. Speaking at the Capitol on Wednesday afternoon, Rubio described a three-step approach that begins with stabilizing the country by seizing and selling between 30 million and 50 million barrels of Venezuelan oil—roughly two months of production—with the proceeds controlled by the United States rather than Venezuela’s interim authorities. “That gives us tremendous leverage,” Rubio said.

Under the plan, he said, the U.S. would next ensure that certain companies have fair access to Venezuela’s energy sector and would work to reintegrate opposition forces. A final phase, which he described only as a transition, would involve integrating opposition parties into a new political framework.

Speaking at a conference with energy executives in Miami, U.S. Energy Secretary Chris Wright suggested that the U.S. would control the movement and sale of the country’s oil “indefinitely.”

“We’re going to … let the oil flow, sell that market to United States refineries and around the world to bring better oil supplies,” Wright said. The U.S. must “have that leverage and that control of those oil sales to drive the changes that simply must happen in Venezuela,” he added.

Funds from the sales, he added, will be placed in accounts controlled by the Trump Administration but would “flow back into Venezuela to benefit the Venezuelan people.”

The Energy Department also said in a fact sheet posted online that the U.S. “is selectively rolling back sanctions to enable the transport and sale of Venezuelan crude and oil products to global markets.”