President Donald Trump is expressing concern over the growing humanitarian crisis in Venezuela and not ruling out military action as a response. Trump told reporters Friday that all options remain on the table in response to anti-democratic actions in Venezuela, including military intervention.

Venezuela’s defense minister called Trump’s talk of a military intervention an act of “craziness” and “supreme extremism.”

The Trump administration has already placed sanctions against Venezuela’s President Nicolas Maduro and numerous other current and former Venezuelan officials in the wake of a crackdown on opposition leaders.

The White House says it’s rejected a request by Maduro to speak to Trump, saying restoring democracy must come first. Venezuela is home to the world’s largest oil reserves and is the third largest petroleum supplier to the U.S.