WASHINGTON (AP) — The United States is considering sanctions against a new list of Venezuelan officials it considers responsible for aggravating the troubled nation’s current crisis.

Secretary of State Rex Tillerson told the House Foreign Affairs Committee Wednesday his office is working with the U.S. Treasury Department on compiling “a very robust list of individuals.”

Tillerson did not name any officials or reveal a timeline for the sanctions.

He said the U.S. faces the challenge of responding in a way that is constructive, rather than providing another tool for officials in President Nicolas Maduro’s government to “justify their current actions.”

The Trump administration has slapped sanctions against eight Supreme Court members as well as Vice President Tareck El Aissami thus far this year.

Venezuela’s recent political upheaval has left nearly 70 dead.