President Donald Trump said Wednesday that U.S. forces have seized a "very large" oil tanker off the coast of Venezuela, a major escalation of the administration's months of efforts to punish the South American petrostate. "As you probably know we have just seized a tanker on the coast of Venezuela, a large tanker, very large, the largest one ever seized actually," Trump said at an event at the White House. "It was seized for a very good reason."