The US continues testing its missile defence systems and producing missiles which are prohibited by the Intermediate-Range Nuclear Force (INF) Treaty aimed at limiting strategic weapons, a Russian military official said on Monday. In an interview with Krasnaya Zvezda newspaper, Sergei Ryzhkov, the head of the National Nuclear Risk Reduction Centre, said that Washington continued to produce a series of target missiles, Xinhua news agency reported. The missiles' tactical and technical characteristics, especially the flight range, belonged to the class of short-range and medium-range missiles, Ryzhkov said. These missiles, according to the officials, were of a general type and can be installed with different warheads as combat ballistic missiles. The development and testing of such missiles posed a precedent for the circumvention of the INF Treaty since these missiles were capable of delivering weapons at ranges limited by the treaty, added Ryzhkov. The INF Treaty was signed in 1987 by the former Soviet Union and the US to ban the development, deployment and testing of ground-launched ballistic or cruise missiles with ranges between 483 km and 5,472 km. Moscow and Washington have repeatedly accused each other of violating the treaty.