NATO announced it joined Russian forces in a computer simulation dubbed Vigilant Skies 2012 that aims to coordinate airspace security over Eastern Europe. The alliance said the simulation could pave the way to live drills over the Black Sea in 2013.
The drill was part of an initiative launched in 2002 that envisions greater transparency and confidence between both sides.
"The purpose is to foster cooperation on airspace surveillance and air traffic coordination against terrorist attacks using civilian aircraft," NATO said.
Al-Qaida terrorists in September 2001 hijacked commercial airliners and crashed them into the World Trade Center in New York and the Pentagon in Washington. A fourth attack was thwarted over Pennsylvania.
In Eastern Europe, Russia has expressed concerns over a missile shield planned by the United States. Moscow says the shield would upset the regional balance of power, though Washington said protection is needed against rogue states such as Iran and North Korea.