There are two people claiming to be Putin on twitter. The first one is @Putin while the 2nd one is @PutinRF_Eng
According to Business Insider http://www.businessinsider.com/vladimir-putin-first-tweet-2014-3 here the first tweet from Original Putin’s English profile on twitter. See his first tweet bellow.
Plus here is Putin’s 1st tweet ever on twitter from his Russian profile.