MOSCOW  Russia on Friday received new proposals from the United States to reduce nuclear arms and provide greater access to the Bush administration’s planned missile defense system, as leaders in Washington moved to calm tensions between the two nations.

Russia has long protested the plans for a missile defense system, which would station radar equipment and 10 interceptors in Poland and the Czech Republic. American officials say the system in designed to counter an attack from Iran, and would not be used against Russian forces

But the missile defense plan was a central topic of Russian President Dmitri A. Medvedev’s state of the nation speech this week. Mr. Medvedev announced that if Washington proceeded with the plan, Russia would respond by stationing short-range missiles and jamming equipment at its western border.

The new American proposals, reported earlier in the Wall Street Journal, would allow Russian military officials to inspect the American installations. Washington has also proposed reducing stockpiles of nuclear warheads in both countries, as well as long-range nuclear weapons.