The U.S. Coast Guard over the weekend was “in active pursuit of a sanctioned dark fleet vessel that is part of Venezuela’s illegal sanctions evasion,” an official told ABC News. “It is flying a false flag and under a judicial seizure order,” the official said at the time.

WEST PALM BEACH, Fla. (AP) — President Donald Trump on Monday delivered a new warning to Venezuelan President Nicolás Maduro as the U.S. Coast Guard steps up efforts to interdict oil tankers in the Caribbean Sea as part of the Republican administration’s escalating pressure campaign on the government in Caracas.

Venezuela said in response to the announced blockade that it rejected Trump’s “grotesque threat.” Venezuela deployed its navy to escort tankers leaving the country’s main oil port from Tuesday evening to Wednesday morning, following Trump’s announcement, according to the New York Times.

Trump is set to announce Monday at 4:30 p.m. from Mar-a-Lago with Pete Hegseth and John Phelan, amid concerns of US escalation in Venezuela.