US Vice President Mike Pence announced sanctions on Friday on 34 vessels of Venezuela's state oil company and two companies that ship crude to Cuba as Washington pushes to oust President Nicolas Maduro.
Venezuela's oil belongs to the Venezuelan people, Pence said in a speech at Rice University in Houston.
Those looking on should know this: All options are on the table. And Nicolas Maduro would do well not to test the resolve of the United States of America, he said.
The United States will continue to exert all diplomatic and economic pressure to bring about a peaceful transition to democracy, he said.
The action is the latest by the United States as it tries to squeeze revenue from the cash-strapped leftist government, which has nonetheless held onto power and enjoys backing from China and Russia.
The Treasury Department said it was designating 34 vessels of state oil company PDVSA as blocked property, meaning that the United States will block all transactions with them.
It also targeted a tanker that ships crude oil from Venezuela to its key ally Cuba, the Despina Andrianna, as well as two shipping companies linked to the vessel - one based in Greece and the other in Liberia.
Treasury Secretary Steven Mnuchin in a statement accused Cuba - a bugbear of the United States for decades -- of propping up Maduro.
The United States remains committed to a transition to democracy in Venezuela and to holding the Cuban regime accountable for its direct involvement in Venezuela's demise, Mnuchin said in a statement.
The United States itself was a key market for Venezuelan oil through Citgo, a subsidiary of PDVSA, but Washington has forced the operator to place earnings in a blocked account.