Russia will deploy advanced S-400 air defense systems during joint military exercises with Belarus in September, a spokesman for the Russian Defense Ministry said. The Union Shield 2011 drills will be held in central and southern Russia on September 16-22. The exercises are aimed at improving combat readiness of the Belarus-Russian regional joint force, as well as raising interoperability between the units of the two countries. Col. Vladimir Drik said on Thursday that S-400 and Pantsir-S air defense systems will be deployed during the operational phase of the exercises at the Ashuluk firing range in the Astrakhan Region. The Union Shield 2011 drills will involve a total of 12,000 troops, as well as up to 50 aircraft and 200 combat vehicles, including 100 tanks. Defense and security cooperation is an important part of the Russian-Belarusian Union State\'s activities. The joint Russian-Belarusian regional military force was formed 10 years ago. Its main objective is to defend the Union State\'s western border and the member states of the Collective Security Treaty Organization (CSTO). Moscow and Minsk also signed an agreement in February 2009 on the joint protection of the Russia-Belarus Union State\'s airspace and the creation of an integrated regional air defense network.