The U.S. military Saturday accused a Russian warship of "high risk" and "highly unprofessional" maneuvers near a U.S. Navy ship in the eastern Mediterranean Sea, the second time in as many weeks that American and Russian ships had such a close encounter on the high seas.

A statement from the U.S. European Command (EUCOM) claimed that the frigate Yaroslav Mudry passed unnecessarily near the guided missile cruiser USS San Jacinto. The statement added that the Yaroslav Mudry navigated in the San Jacinto's wake. 

EUCOM said the U.S. cruiser was not threatened and maintained its course and speed. However, the statement said the Russian maneuver was "contrary to international maritime regulations."

"These actions can unnecessarily escalate tensions between countries, and could result in dangerous miscalculations or accidents," the EUCOM statement said.

Reuters reported that at the time of the incident, the San Jacinto was carrying out operations against ISIS in Iraq and Syria along with the aircraft carrier USS Dwight D. Eisenhower. 

The latest incident occurred 13 days after another incident between U.S. and Russian forces in the Mediterranean Sea. On June 17, defense officials tell Fox News, the Russian frigate Neustrashimyy maneuvered close to the USS Gravely, a destroyer that was protecting another U.S. aircraft carrier, the USS Harry Truman, while the Truman was launching anti-ISIS airstrikes.

One official said the Neustrashimyy had raised the day shape “ball-diamond-ball” on her mast, the international signal a ship displays when restricted in her ability to maneuver, when it took position two nautical miles off Gravely’s starboard quarter.

 The Russian ship repeatedly asked Gravely over VHF radio, a common “bridge-to-bridge” radio required of all vessels at sea, to maintain a safe distance, while Neustrashimyy continued to maneuver to get closer to Gravely.

As Gravely changed course and speed, Neustrashimyy also changed course and speed, according to one official. At one point, the Neustrashimyy came within 315 yards from the U.S. destroyer and five nautical miles to the American aircraft carrier

The incidents are the latest in a string of “highly provocative” actions from Russia to try to intimidate the United States, according to the officials. In April, Russian jets buzzed a U.S. Navy destroyer in the Baltic Sea conducting a series of high speed passes at close range more than 30 times. A State Department spokesperson said earlier this week harassment of U.S. diplomats in Moscow by Russian spies had “increased significantly.”

Fox News' Lucas Tomlinson contributed to this report.