US allegations of Russian non-compliance with the Intermediate-Range Nuclear Forces Treaty (INF) are based on a ground-launched missile system the United States believes is under development, and not systems currently fielded by Russia, US Under Secretary for Arms Control said Wednesday.

"We've been very open and public since July, when we published our compliance report, that Russia is not in compliance with the INF Treaty, and the reason is a ground-launched cruise missile that has been tested and is in development in the Russian Federation," Rose Gottemoeller said at a Wednesday conference at the Brookings Institute in Washington.

US concerns about INF non-compliance are not related to the deployment of either Iskander missiles or X-101 missiles, contrary to media rumors, Gottemoeller stated, though provided no other specifications.

Whether or not the system is deployed is inconsequential to the terms of the INF Treaty, Gottemoeller explained.

"If they're seen being tested, if they're in development, then they're not in compliance with the INF Treaty," she said, adding that these were the specific concerns raised in the US non-compliance report published in July.

In late July, the Russian Foreign Ministry published a report, pointing to three US systems believed to be in violation of the INF Treaty. Those systems include the use of drones, which the Russian Foreign Ministry states has similar characteristics to intermediate-range missiles, and the MK-41 launch systems the United States is testing and deploying in Romania and Poland.

In response, Gottemoeller stated that she is "completely confident" the United States is "in full compliance with our INF Treaty obligations."

The State Department is preparing to release a fact sheet of unclassified information demonstrating why they believe the three systems named by the Russian Foreign Ministry are in compliance with the INF, she noted.

Russian officials have repeatedly stated that US accusations of INF non-compliance are not supported by facts or evidence. In a December 9 interview with RIA Novosti, Russian Foreign Minister Sergei Lavrov stated that "the US has provided no evidence so far" of Russian violations of the treaty.

The United States and Soviet Union enacted the INF Treaty in 1988 banning nuclear and conventional missiles with a range of 500 to 5500 kilometers (310 to 3417 miles).