The United States is urging Russia to ensure that upcoming joint Russian-North Korean naval exercises are not interpreted by the North as a license to ignore international concerns about Pyongyang's rogue nuclear weapons programs.

The U.S. concern came Thursday in a State Department statement — two days after Moscow said it would hold the unprecedented maneuvers next year. A Russian military spokesman said the joint drills will focus on search and rescue operations. He did not offer details.

The U.S. statement also said the maneuvers should not obscure what it called “the necessity of Pyongyang to do what is necessary to return to six party talks” on its nuclear activities.

The United States and South Korea regularly hold joint military exercises, including annual naval drills. In August, the two allies conducted maneuvers in the Yellow Sea, over strong North Korean objections and threats of military retaliation against its southern neighbor.

U.S. commanders have described their joint exercises at defense-oriented.

North-South tensions remain taut along the Korean coastline of the Yellow Sea — the scene of several deadly naval confrontations in the past decade.