NATO's leader called Friday for the U.S., Russia and NATO to join their missile defense systems against potential nuclear threats from Asia and the Middle East.
Secretary-General Anders Fogh Rasmussen said that the old foes must forget their Cold War animosity.
"We should explore the potential for linking the U.S., NATO and Russia missile defense systems at an appropriate time," Fogh Rasmussen said. "Both NATO and Russia have a wealth of experience in missile defense. We should now work to combine this experience to our mutual benefit."
His appeal for unity came a day after President Barack Obama announced the U.S. was scrapping a Bush-era plan for an Eastern European missile defense shield.
The now-shelved plan had been a major irritant in relations with Russia.
Fogh Rasmussen also acknowledged NATO and Moscow have failed to jointly take on global security threats, including terrorism.
On Thursday, the U.S. said the decision to abandon the missile defense shield was due to a change in the U.S. perception of the threat posed by Iran.
U.S. intelligence decided short- and medium-range missiles from Iran now pose a greater near-term threat than the intercontinental ballistic missiles the Bush plan addressed.
A new missile-defense plan would rely on a network of sensors and interceptor missiles based at sea, on land and in the air.