The Blues skipper missed the Premier League finale against Fulham with a tight hamstring.
The outlook for David Nugent also looks brighter.
The former England striker suffered a slight groin strain while warming-up for the reserves last week.
However, Nugent was set to take part in some aspects of training.
He is expected to return to full training by the end of the week and declare himself fit for FA Cup final selection.
Elsewhere, David James will play against Cardiff having now fully recovered from the calf injury which kept him out for three matches.
The England keeper is back in training and been given the Wembley go-ahead.
Kanu picked up a dead leg on Sunday but medical staff are not overly concerned and he will be fine to lead Pompey's attack.
Meanwhile, Noe Pamarot and John Utaka suffered no reaction following their return from injuries against Roy Hodgson's side.
It means, aside from Linvoy Primus and the cup-tied Jermain Defoe, Pompey will be at full strength for the FA Cup final.