Tevez becomes the most expensive player in British history and the fifth highest in the world.
The Times says City's billionaire Arab owners have agreed to pay almost twice the £25.5 million fee widely reported to have changed hands. An initial £15 million payment is to be followed by two additional sums of £16 million.
Another £3.5 million will be paid if City win the Champions League while Tévez is at the club - an improbable scenario, but Sheikh Mansour has already shown the lengths to which he is prepared to go to transform the club from perennial underachievers into contenders for the biggest prizes.
Tevez's investors stand to make an estimated profit of at least £50 million from an assortment of fees received for a player whose "economic rights" they originally bought from Boca Juniors for £14 million in 2004.
They are understood to include a fee of £4.5 million from West Ham, where Tévez spent the 2006-07 season, a £9 million payment from Manchester United to cover the cost of the player's two-year "loan" at Old Trafford and now the sum from City.