The reason is that to turn into the Leader of the Opposition, the previous President must turn into a MP and the main path for it to happen is for him to take his seat as a National List MP in the wake of making an alternate Parliamentarian leave from the seat.
Rajapaksa can't be taken in as a National List MP as his name was not on the National List of the Party at the 2011 Parliamentary race.
Therefore a substantial number of senior SLFP stalwarts need Nimal Siripala de Silva to be delegated as the Opposition Leader.
However the move to accumulate Rajapaksa into Parliament is still in progress as one National List MP in the United People's Freedom Alliance (UPFA) has agreed to clear his seat and clear a path for the vanquished ex-strongman.
