The U.S. Navy chief said Monday that Russia's actions in the Baltic Sea have triggered further problems between the two countries. Adm. John M. Richardson, however, also said that he hoped for a “normalization” of relations with Moscow in the Baltic, where Russian jets buzzed a U.S. warplane and a ship recently.

“It just increases the chance for some kind of a tactical miscalculation,” Richardson said, according to Agence France-Presse . “It just sort of raises the overall tension in the region, so we look for sort of normalization there.”

Richardson also urged Russia to follow a 192 maritime agreement, signed by the United States and Soviet powers to avoid naval mishaps and stop any such events.

“We continue to advocate for that,” Richardson said, adding that the he did not think Moscow was being provocative. “I don't think the Russians are trying to provoke an incident,” he said. “I think they are trying to send a signal.”

Richardson’s comments came after a Russian Su-27 intercepted a U.S. Air Force RC-135 aircraft flying a reconnaissance mission in international airspace over the Baltic Sea Friday. The Pentagon condemned the incident, calling the interception “unsafe and unprofessional.” But Russia defended the action, saying it sent the fighter jet close because the American plane had turned off its transponder, which is needed for identification.

Last month, a Russian Su-24 military jet came within 30 feet of U.S. naval destroyer, the USS Donald Cook, in the Baltic Sea, raising concerns over the Russian flight maneuvers.

“There have been repeated incidents over the last year where Russian military aircraft have come close enough to other air and sea traffic to raise serious safety concerns, and we are very concerned with any such behavior,” Pentagon spokesman Commander Bill Urban said.