The U.S. amphibious warship USS Carter Hall (LSD-50) and Marines have arrived over the weekend in Romania for joint drills.

The bilateral Spring Strom 2017 exercise pairs elements of the 24th Marine Expeditionary Unit (MEU) with the Romanian military to test how well U.S. Marines and Romanians work together.

The exercise, which runs until Wednesday, includes 450 Marines and 750 Romanian troops, U.S. Landing Craft Air Cushion (LCAC) hovercraft and Amphibious Assault Vehicles.

Carter Hall entered the Black Sea on March 17.

The U.S. and Romania have increased military cooperation since the 2014 forced annexation of Crimea from Ukraine by Russia.

Carter Hall and the 24th MEU are part of the Bataan Amphibious Ready Group which also includes bigdeck amphibious warship USS Bataan (LHD-5), USS Mesa Verde (LPD-19).

“The 24 MEU consists of more than 2,200 Marines, which also includes a Ground Combat Element, Battalion Landing Team 3rd Battalion, 6th Marine Regiment, Marine Medium Tiltrotor Squadron 365 (Reinforced), and Combat Logistics Battalion 24 and the MEU command element. The 24 MEU spent 26 weeks training in mission areas such as security operations, humanitarian relief, and amphibious raids,” read a March Navy release.