Russia must halt its covert development of a banned cruise missile system or the United States will seek to destroy it before it becomes operational, Washington's envoy to NATO said on Tuesday.

The United States believes Russia is developing a ground-launched system in breach of a Cold War treaty that could allow Russia to launch a nuclear strike on Europe at short notice, but Moscow has consistently denied any such violation.

U.S. Ambassador to NATO Kay Bailey Hutchison said Washington remained committed to a diplomatic solution but was prepared to consider a military strike if development of the medium-range system continued.