Last week, U.S. State Department representative Ellen Tauscher said that in the interests of transparency the U.S. had extended an invitation to Russia to attend a demonstration of the Standard Missile-3 interceptor, Space News reported. Tauscher said the U.S. was not offering Russia telemetry data or any classified information.
In an interview with Interfax published Tuesday, Ryabkov said the Russian government wanted more than a one-off opportunity to observe the system in action.
"At the moment, we do not see why our participation is needed in these events. If we accept this invitation, how will that help to alleviate our concerns? The issue is not being able to observe some event a single time, but to have the opportunity to evaluate independently what is going on," Ryabkov said.
"We have not yet been able to agree on that," he said.
Russia has insisted on written guarantees from the U.S. government that the BMD system will not be directed against its forces.