Putin said he agreed with Medvedev on the "castling" 4 years ago

Association of a possible future president with the stagnation of the Brezhnev era irrelevant, Putin said. "I do not recall that post-war Soviet leadership, the leaders of the Soviet post-war work as intensively as I do it or the current president Dmitry Medvedev," - said the prime minister. Russian News Service
 Castling the Putin-Medvedev tandem has been conceived four years ago. This was stated by Prime Minister Vladimir Putin of Russia, adding that the issue was settled between him and President Dmitry Medvedev, has not been resolved but the citizens of Russia, who will vote in the election. Radio Liberty
The full version of the interview show TV channel "Russia 24" on October 17 in 23 hours. Vladimir Putin admitted that they Dmitry Medvedev four years ago agreed that the option's quite possible, "if we go through a period of rather heavy trials." BBC News