Russia's President Vladimir Putin said last night a new radar station near St. Petersburg was the first stage in a large-scale air defence programme, Russian agencies reported.
"This is the first step in a large-scale programme in this sphere that will be carried out to 2015," Mr Putin was quoted as saying during a visit to St. Petersburg. He did not elaborate.
It was the first public announcement of such a programme. Russia has said it will beef up its air defence system in response to the United States's initiative to station elements of a missile shield near Russia's borders.
The Voronezh-type radar station in the village of Lekhtusi about 50 km (30 miles) north of St. Petersburg has been operational since December 2006 and can monitor the territory between the North Pole and Africa.
"This is what I call modern development of armed forces. A lot more effective, a lot more reliable," Mr Putin was quoted as saying.
The United States wants to base interceptor missiles and a radar system in Poland and the Czech Republic, saying it needs protection against missile attacks from "rogue states" like Iran and North Korea.
Russia has reacted furiously, saying the plan will upset a delicate strategic balance and that the missile shield is against Russia, not "rogue states". It has threatened to target its own missiles at Europe, prompting talk of a new Cold War.
Mr Putin has proposed Washington drop the idea, offering in return that the US military use a Voronezh-type station under construction in southern Russia and a centre in Moscow to share data on attacks. The United States has reacted cautiously.