Russia's foreign ministry said Tuesday it would seek defence safeguards from the United States following Romania's decision to host US interceptors for a proposed European missile defence shield.

"In this situation, US legal guarantees on their intention not to deploy a missile defence system aimed at the strategic nuclear forces of Russia is becoming even more relevant," news agencies quoted a ministry statement as saying.

"Moreover, we are convinced... that we need to immediately begin agreeing a European missile defence conception and architecture, including from the standpoint of its impact on regional and global security," Russia said.

The United States and Romania agreed on Tuesday to place US missiles at a Soviet-built airbase in the south of the Eastern European country -- the first to receive interceptors for the proposed pan-European shield.

Moscow fears that the system -- which Washington says is aimed at states such as Iran -- could one day be transformed into an offensive space-based weapon that could be aimed at western and southern Russia.

US and Russian officials held a new round of consultations in Brussels on Monday aimed at addressing Moscow's various concerns.

The Moscow statement expressed "disappointment" that the system was moving ahead despite the high-level Russian-US negotiations.

And it accused the United States of making the European shield just the first part of a future global missile defence system -- something it rarely accuses Washington of trying to build in public statements.

"Practical steps on creating the European segment of the global US missile defence system are being undertaken irrespective of the Russian-US dialogue," the Russian foreign ministry observed.

Russia is seeking a direct role in the European system's operation -- achieving a level of clearance that would allow it to help decide which nations posed a threat and when an actual interceptor missile should be fired.

Russia's Deputy Defence Minister Sergei Ivanov said on a visit to Washington last month that "we insist on only one thing. That we are an equal part of it."