WASHINGTON (AP) President Donald Trump has declared drug cartels operating in the Caribbean are unlawful combatants and says the United States is now in a “non-international armed conflict,” according to a Trump administration memo obtained by The Associated Press on Thursday.

A U.S. official familiar with the matter who was not authorized to comment publicly said the Congress was notified about the designation by Pentagon officials on Wednesday.

The move comes after the U.S. military last month carried out three deadly strikes against alleged drug smuggling boats in the Caribbean. At least two of those operations were carried out on vessels that originated from Venezuela.

Pentagon officials could not provide a list of the designated terrorist organizations at the center of the conflict, a matter that was a major source of frustration for some of the lawmakers who were briefed, according to the U.S. official.

Democrats have been pressing Trump to go to Congress and seek war powers authority for such operations. The official added that the Republican administration now faces criticism that it is effectively waging a secret war against secret enemies, without the consent of congress.

The White House did not immediately respond to a request for comment.

What the administration laid out at the closed-door classified briefing was perceived by several senators as pursuing a new legal framework that raised questions particularly regarding the role of Congress in authorizing any such action, the official familiar with the matter said.

As the administration takes aim at vessels in the Caribbean, senators and lawmakers of both major political parties have raised stark objections. Some had previously called on Congress to exert its authority under the war powers act that would prohibit the administration’s strikes unless they were authorized by Congress.