The United States and Russia have agreed to the largest "spy swap" since the Cold War ended.

A New York judge ordered the immediate deportation of 10 people who pleaded guilty to acting as agents for a foreign government without permission.

Following that, Dmitry Medvedev, the Russian president, pardoned four convicted foreign spies - after they submitted a plea for pardon and admitted their guilt - so they could be exchanged for the 10.

Medvedev and his US counterpart, Barack Obama, have approved the swaps.

Al Jazeera's Nick Spicer reports. (July 09, 2010)