Victory Day military parade in Moscow (17 images)

MOSCOW, May 9 (UPI) -- Soldiers from four NATO countries marched for the first time in Russia's annual Victory Day parade marking the victory in World War II, observers said.

Troops from Britain, France, Poland and the United States marched alongside 10,000 Russian forces while about two dozen world leaders attended the 65th anniversary, the BBC reported Sunday. The parade also featured tanks, ballistic missiles and a fly-over of 127 aircraft.

Russian President Dmitry Medvedev told spectators lessons from World War II "urge us to show solidarity."

"Peace is still fragile and it is our duty to remember that wars do not start in an instant," Medvedev said. "It is only together that we shall be able to counter modern threats."

Victory Day parades involving more than 102,000 service personnel and more than 200,000 veterans were conducted in 36 Russian cities, Russian news agency RIA Novosti reported.

Medvedev said the march on the Red Square "symbolizes our readiness to defend peace, to prevent the revision of the results of the war, to prevent new tragedies."