He can't sign a normal contract because his Arsenal contract doesn't expire until June 30th. For him to sign a normal contract now, Arsenal would have to release him and we'd have to pointlessly pay his wages for a couple of weeks.
City wouldn't announce him if he hadn't signed a legally binding pre-contract.
As for Fernando, apparently there is a dispute over money between him and Porto (I'd guess loyalty bonus), nothing that would seem to threaten his move to City since Porto and City have agreed terms.
City wouldn't announce him if he hadn't signed a legally binding pre-contract.
Manchester City are delighted to announce that Bacary Sagna will join the Club for next season.
As for Fernando, apparently there is a dispute over money between him and Porto (I'd guess loyalty bonus), nothing that would seem to threaten his move to City since Porto and City have agreed terms.