As per the latest reports, they are not going to have anybody as the Finance Minister but the PM will himself hold the portfolio of FM. He will be assisted by Montek Singh Ahluwalia, C. Rangarajan and other experts which means that practically they will be doing the job but PM will be officially responsible as FM.
Either Ahluwalia or Rangarajan would be almost equally well suitable for this job.
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Who ever be the new Finance Minister, the Nation will go to the polls in 2014. So the next two budgets have to be people friendly.
As of now, P.Chidambaram can be considered for the post as he has proven his ettle as the Finance Minister. Being an Economist, Dr.MMS may not be a people friendly FM. And Dr.MMS's preference is for Montek Singh Ahluwalia, as the Finance Minister. Mr.Ahluwalia as the new FM may no be a wise choice as he may puish for reforms at a faster pace and exposing the lower strata of society to more and more economic woes.. So, Mr.Chidambaram may be a wise choice, I suppose