Also, there are many other important aspects of evidence, which the prosecution has to adduce to expose the terrorist infrastructure of the perpetrators of the crime, he said, adding they will not let Kasab succeed in his 'motive' of escaping with lesser punishment.
"What Kasab has told the court is not the entire story. He has partially admitted his guilt," Nikam told PTI.
Although Kasab has made a confession, it is the prosecution's discretion to marshal further evidence, he said.
"Kasab has not fully disclosed his involvement. He has played with the sentiments of the common man by minimising his role in the crime and throwing responsibility on slain terrorists for the mayhem on November 26 last year," the prosecutor said.
Kasab had earlier admitted his guilt before a magistrate, but later denied his role in the November 26 terror attacks. Now he has confessed in the trial court about his participation in the terror strikes, but has deviated from his earlier confession.
"He is like a joker in a circus and should not be taken seriously," Nikam, who has handled several high profile cases including that of the 1993 Mumbai [ Images ] blasts, said.
Kasab, Nikam claimed, has not disclosed in his confession on Monday that he had killed police constable Tukaram Omble although he had said this earlier before a magistrate.
On the other hand, he confessed that terrorist Abu Ismail had led the attacks at the Chhatrapati Shivaji railway Terminus and the Cama hospital [ Images ] killing many people, thereby shifting the blame onto Ismail, Nikam said.
Kasab has said the trial should be wound up and he should be punished. "This clearly indicates that he wants lesser punishment, but the prosecution will jeopardise his motives," Nikam said.
"Unfortunately, some politicians, while reacting to Kasab's confession, have been swayed by the admission of his guilt, but they must be careful to see through his designs," the prosecutor said.
All those things, which Kasab omitted in the confession made to the court on Monday would have to be proved by the prosecution.
"Kasab would be confronted with these contradictions and if he does not admit then the prosecution would lead evidence to prove them in court," Nikam said.
The trial is not only against Kasab, but also against Faheem Ansari and Sabauddin Ahmed who allegedly provided maps of targets to the perpetrators of the crime, the lawyer said.
The trial is also against the 27 absconding accused believed to be in Pakistan who had planned and executed the terror attacks. Hence, Kasab's confession at this stage would not put an end to the trial, Nikam asserted.