UNITED NATIONS - A senior U.S. State Department official on Tuesday said diplomatic engagement is under way on tensions between Armenia and Azerbaijan, adding that U.S. Secretary of State Antony Blinken would likely get involved.

Azerbaijan launched "anti-terrorist activities" in the Nagorno-Karabakh region on Tuesday, saying it wanted to restore constitutional order and drive out what it said were Armenian troops, a move that could foreshadow a new war.

(Reporting by Doina Chiacu and Humeyra Pamuk; Writing by Daphne Psaledakis; Editing by Howard Goller)