The guided-missile destroyer Ross arrived in the Bulgarian port of Varna this week for another round of military exercises in the Black Sea.

Maneuvers alongside the Bulgarian navy were slated to begin Wednesday and are designed to “strengthen interoperability with NATO allies and partners and demonstrate the collective resolve to Black Sea security," according to a prepared statement released by the U.S. 6th Fleet.

Based in Rota, Spain, the Ross is the fourth U.S. warship to visit the Black Sea since Jan.1 and this bilateral exercise comes amid simmering tensions with Russia across the region.

In 2014, Moscow annexed Kiev’s Crimean Peninsula, sparking an ongoing civil war in Ukraine’s eastern provinces.

In November, Russian forces seized three Ukrainian vessels and their crews in the Kerch Strait, escalating the conflict.

The Russian state media outlet Tass reported Monday that Moscow’s Black Sea Fleet “is monitoring the movement of the USS Ross destroyer,” with the patrol vessel Vasily Bykov and reconnaissance ship Ivan Khurs specifically detailed to shadow the warship.

On Feb. 26, a sister Arleigh Burke-class destroyer — Donald Cook — made a port call in the Ukrainian port of Odessa following a visit to the Georgian port of Batumi.

The Ross is scheduled to visit Georgia and conduct exercises with Tbilisi’s forces, too.

Backing separatist movements in South Ossetia and Abkhazia, in 2008 Russia battered Georgia in a brief war.

“U.S. 6th Fleet assets routinely operate in the Black Sea and Ross is part of our long-standing effort to exercise and engage in the region," said 6th Fleet commander Vice Adm. Lisa M. Franchetti in the release.

"Having the opportunity to conduct training alongside our NATO allies and partners enhances our ability to work together at sea across the full spectrum of maritime operations.”