KYIV, Sept. 24 - Ukraine and Russia intensified standoff as the Sea of Azov is becoming a new area of contention increasing military presence in the area, Stratfor, a private U.S. strategic analysis firm, reported Monday.

The military buildup could also lead to growing economic disruption of shipping in and out of the sea, the firm reported.

Russia is stronger than Ukraine on the sea, but robust U.S. support for Kyiv could alter the situation in the area, Stratfor said.

“The conflict between Ukraine and Russia has so far been restricted to ground battles over control of eastern Ukraine,” Stratfor reported. “Recent developments, however, suggest that the war — now in its fifth year — could soon spread to the sea.”

The comments come days after Russian naval forces resorted to unsafe military practices against two Ukrainian naval ships as Ukraine is seeking to establish a naval base in Berdiansk on the Sea of Azov.

The Ukrainian search and rescue ship A500 Donbas and seagoing tug A830 Korets passed through the Straight of Kerch heading to Berdiansk on Sunday, but were followed by Russian naval ships that had resorted to “extremely dangerous” maneuvering, according to the Ukrainian navy.

In terms of overall naval deployments, “Russia is in a much stronger position than Ukraine” in the area around the Black Sea, according to Stratfor.

The Ukrainian navy possesses 66 combat and auxiliary naval units, as well as about 11,000 service members. In contrast, Russia's Black Sea Fleet, which is headquartered in Sevastopol, boasts more than 2,800 vessels and 25,000 service members.

“The disparity is not just in quantity but in quality as well: On average, Ukraine's vessels are much smaller and weaker than those of their Russian adversaries, “ Stratfor said.

At present, Ukraine does have a presence on the Sea of Azov, but the deployments are relatively small, featuring just two coast guard detachments in Berdyansk and Mariupol that use only small and outdated patrol boats.

The Sea of Azov is of critical importance to Ukraine's economy — perhaps even more so since Kyiv lost Crimea, because 80 percent of the country's exports now pass through the body of water.

A bridge that Russian built to connect its mainland with the occupied Crimea has design that is too low for Panamax vessels, which accounted for about 23 percent of all ship traffic in the area in 2016.

As a result, cargo flows from Mariupol have dropped 27 percent, from more than 8.9 million tons in 2015 to 6.5 million tons in 2017; from Berdyansk, they have fallen 47 percent, from 4.5 million tons in 2015 to just 2.4 million tons in 2017. Before the Ukraine conflict, freight traffic was much higher, with 15 million tons of cargo passing through Mariupol in 2013 alone.

In recent months, Russia has been interrupting even more freighter traffic from Ukraine, stopping as many as 148 ships sailing to Ukrainian ports between May and mid-July, according to Ukraine's infrastructure minister, Volodymyr Omelyan.

Russia's actions are costing Ukraine $20 million to 40 million every year, and although they have not yet led to supply shortages, the costs could pile up in the future, according to Stratfor. (tl/ez)