MOSCOW, April 3 (Xinhua) -- Russian and Belarussian experts Monday started a five-day observation flight over the Polish territory, a Russian official said.
The flight, with a maximum range of up to 1,400 km, will be carried out along the coordinated route by a Russian An-30B jet in accordance with the Treaty on Open Skies, said Sergei Ryzhkov, head of the Russian Defense Ministry's Nuclear Risk Reduction Center.
Polish experts on board the plane are in charge of controlling the observation equipment, he added.
During the same period, experts from Denmark, Sweden and Britain will conduct an observation flight over Russia, according to Ryzhkov.
The Treaty on Open Skies was signed in March 1992 and became one of the major confidence-building measures in Europe after the Cold War. It took effect in 2002 and currently has 34 state parties, including Russia and most members of the North Atlantic Treaty Organization (NATO).