Russia and the US have completed the biggest spy swap since the Cold War at Vienna airport.
The White House has said that the head of the CIA was responsible for the negotiations leading to the spy swap.
Director of the Central Intelligence Agency Leon Panetta led the talks.
A spokesperson for the White House has said that 'the US government came up with the four individuals to be freed by the Russians.
The reasons that they sought their release was based on humanitarian, health concerns, and other reasons that we put forward to the Russians,’
Ten Russian agents deported by US authorities hours earlier were exchanged for four US spies jailed in Russia.
Two jets - one from Russia, one from the US - brought the spies to the Austrian capital and parked next to each other on the runway.
Covered steps placed over the main doors to the two jets hid the exchange from media gathered at the airport.
The two flights took-off within 15 minutes of each other after making the exchange that kept a thaw in US-Russian ties on track.
A government jet carrying the 10 Russian spies took them back to Moscow Domodedovo Airport, officials said.
A source in the Russian intelligence services said in a statement they were returning 'to the motherland'.
The US plane made a brief stop at the Brize Norton airbase in central England before taking off again, British media reported.
Russia confirmed that a deal had been agreed with the US aiming to end the spy scandal.
The Russian foreign ministry said the bargain involved the 'return to Russia of 10 Russian citizens accused in the United States, along with the simultaneous transfer to the United States of four individuals previously condemned in Russia.'
Ten guilty pleas in New York
The ten Russian agents had earlier left New York after pleading guilty to living undercover in the US. They were ordered to leave the US and to never return.
The Russian spy ring in the US appeared to have been amateurish and made little impact in the decade since being formed.
‘No significant national security benefit would be gained from the prolonged incarceration in the United States of these ten unlawful agents,’ State Department spokesman Mark Toner said.
Yesterday in New York, Federal Judge Kimba Wood rushed through the procedure, sentencing them to ‘time served’ within minutes of hearing them plead guilty.
Speaking in English, all but one of them, Vicky Pelaez, admitted they were Russian.
Several also acknowledged using fake names to hide in deep cover.
The defendants living as Richard and Cynthia Murphy were really Vladimir and Lydia Guryev, while Donald Heathfield's true name was revealed to be Andrey Bezrukov.
Pelaez, unlike the others, is a US citizen.
But a senior US official said that as part of the deal, she agreed never to return to the US without the authorisation of the attorney general.
The plea agreement also states that if any of the suspects want to profit in the future by selling details of their case, the proceeds would go to the US government, the official added.
Russia went to great lengths to ease the deal, sending consular officials to the detained ten to describe ‘the life these defendants might be returning to back in Russia,’ a US prosecutor said.
Pelaez, the court heard, was promised free housing in Russia, a $2,000 monthly stipend ‘for life,’ and visas for her children to visit.
Outside the courthouse, a lawyer for Anna Chapman, the founder of a successful New York real estate company, said his client was ‘glad to be released from jail’ but ‘unhappy that it has probably destroyed her business and that she has to return to Moscow.’
Four US spies
US officials said the four people released in Russia were forced to confess to charges there as part of the deal.
‘I leave it to the individuals involved to tell their stories, including their years of imprisonment. But in order to get out of jail, they had no choice but to sign the Russian government oath,’ the US official said.
The four, who had been serving jail terms in Russia for passing secrets to the West, were pardoned by Russian President Dmitry Medvedev.
Arms control expert Igor Sutyagin was one of those exchanged.
Also exchanged was Sergei Skripal, a former colonel with Russian military intelligence sentenced in 2006 to 13 years jail on charges of spying for Britain.
The remaining two were Alexander Zaporozhsky, a former employee of the Russian Foreign Intelligence Service who was jailed for 18 years for espionage in 2003, and a fourth called Gennadi Vasilenko.
Watch the ten Russian agents boarding a plane in New York
