A Russian deputy foreign minister has warned that an attack on Iran could have what he described as "catastrophic" consequences for regional and possibly international relations.
The warning, by Gennady Gatilov, comes shortly after the UN nuclear watchdog expressed disappointment after its representatives' visit to Iran, saying Tehran refused to give them access to a military complex at Parchin.
The military site has been linked to Iran's nuclear program, which the West suspects is aimed at making atomic bombs. Tehran denies anything but civilian intentions for its nuclear activities.
The United States and Israel have not ruled out a military strike on Iran to resolve the crisis.
Tehran's traditional ally, Russia has helped the country build and fuel its Bushehr nuclear plant.