MOSCOW, Dec. 15 (Xinhua) -- Moscow has not received any response from Washington to Russian Defense Minister Sergei Shoigu's proposal to discuss disagreements concerning the Intermediate-Range Nuclear Forces (INF) Treaty, the Russian Defense Ministry said in a statement on Saturday.

The proposal was related to one of the two notes recently sent by Shoigu to U.S. Secretary of Defense James Mattis. The other note was about Syria, according to the ministry.

"It has been emphasized that Russia is ready for an open and detailed dialogue with the Pentagon on all the pressing bilateral issues. However, three days after the notes were received, the Russian Defense Ministry has not received even a formal response to this proposal from the U.S. military," the ministry said in the statement.

The lack of a U.S. response showed Washington's unwillingness to maintain a professional dialogue with Moscow on solving pressing regional and global security issues, the ministry said.

In early December, U.S. Secretary of State Mike Pompeo said that the United States would suspend its obligations under the INF Treaty in 60 days unless Russia returns to full compliance with the agreement. Moscow has repeatedly denied that it has violated the treaty.

The INF Treaty was signed in 1987 between the Soviet Union and the United States on the elimination of intermediate-range and shorter-range missiles.

Moscow and Washington have been accusing each other of violating the arms control agreement in recent years amid increasing tensions between the two countries.